diff --git a/src/commands/generate/types/__tests__/management-api.test.ts b/src/commands/generate/types/__tests__/management-api.test.ts
index 338c2ae..3ff1c21 100644
--- a/src/commands/generate/types/__tests__/management-api.test.ts
+++ b/src/commands/generate/types/__tests__/management-api.test.ts
@@ -126,6 +126,7 @@ describe('management-api', () => {
         referencedApiEndpoint: undefined,
         customFieldCreatedAt: undefined,
         customFieldCreatedAtList: undefined,
+        selectItems: undefined,
       },
       {
         fieldId: 'related',
@@ -135,6 +136,7 @@ describe('management-api', () => {
         referencedApiEndpoint: 'articles',
         customFieldCreatedAt: undefined,
         customFieldCreatedAtList: undefined,
+        selectItems: undefined,
       },
     ]);
     expect(schema.customFields).toEqual([
@@ -150,12 +152,47 @@ describe('management-api', () => {
             referencedApiEndpoint: undefined,
             customFieldCreatedAt: undefined,
             customFieldCreatedAtList: undefined,
+            selectItems: undefined,
           },
         ],
       },
     ]);
   });
 
+  it('fetchApiSchema は selectItems を文字列配列/オブジェクト配列の両形式でパースする', async () => {
+    setMockFetch(async () => {
+      return new Response(
+        JSON.stringify({
+          apiEndpoint: 'product',
+          apiType: 'LIST',
+          apiFields: [
+            {
+              fieldId: 'color',
+              kind: 'select',
+              required: true,
+              multipleSelect: false,
+              selectItems: ['Red', 'Blue', 'Green'],
+            },
+            {
+              fieldId: 'size',
+              kind: 'select',
+              required: false,
+              multipleSelect: true,
+              selectItems: [{ value: 'S' }, { value: 'M' }, { value: 'L' }],
+            },
+          ],
+          customFields: [],
+        }),
+        { status: 200, headers: { 'content-type': 'application/json' } },
+      );
+    });
+
+    const schema = await fetchApiSchema(FIXTURE_CONFIG, 'product');
+
+    expect(schema.apiFields[0]?.selectItems).toEqual(['Red', 'Blue', 'Green']);
+    expect(schema.apiFields[1]?.selectItems).toEqual(['S', 'M', 'L']);
+  });
+
   it('401 応答時は API キー向けの専用エラーメッセージを返す', async () => {
     setMockFetch(async () => new Response('invalid key', { status: 401, statusText: 'Unauthorized' }));
 
diff --git a/src/commands/generate/types/__tests__/type-generator.test.ts b/src/commands/generate/types/__tests__/type-generator.test.ts
index f737a68..a6ea931 100644
--- a/src/commands/generate/types/__tests__/type-generator.test.ts
+++ b/src/commands/generate/types/__tests__/type-generator.test.ts
@@ -57,6 +57,267 @@ describe('renderDefinitionsFile', () => {
     expect(source).not.toContain('SettingsListResponse');
   });
 
+  it('select フィールドは multipleSelect に関わらず常に string[] を生成する', () => {
+    const source = renderDefinitionsFile([
+      createTarget('product', {
+        apiType: 'LIST',
+        schema: createSchema({
+          apiFields: [
+            { fieldId: 'category', kind: 'select', required: true, multipleSelect: false },
+            { fieldId: 'tags', kind: 'select', required: false, multipleSelect: true },
+          ],
+        }),
+      }),
+    ]);
+
+    expect(source).toContain('category: string[];');
+    expect(source).toContain('tags?: string[];');
+    expect(source).not.toMatch(/category: string;/);
+  });
+
+  it('select フィールドに selectItems がある場合、文字列リテラルユニオンの配列型を生成する', () => {
+    const source = renderDefinitionsFile([
+      createTarget('product', {
+        apiType: 'LIST',
+        schema: createSchema({
+          apiFields: [
+            {
+              fieldId: 'size',
+              kind: 'select',
+              required: true,
+              multipleSelect: false,
+              selectItems: ['S', 'M', 'L', 'XL'],
+            },
+          ],
+        }),
+      }),
+    ]);
+
+    expect(source).toContain('size: ("S" | "M" | "L" | "XL")[];');
+  });
+
+  it('relationList フィールドは参照先エンドポイントの Content 型を配列で生成する', () => {
+    const source = renderDefinitionsFile([
+      createTarget('article', {
+        apiType: 'LIST',
+        schema: createSchema({
+          apiFields: [
+            {
+              fieldId: 'relatedPosts',
+              kind: 'relationList',
+              required: false,
+              multipleSelect: false,
+              referencedApiEndpoint: 'blog',
+            },
+            {
+              fieldId: 'authors',
+              kind: 'relationList',
+              required: true,
+              multipleSelect: false,
+            },
+          ],
+        }),
+      }),
+    ]);
+
+    expect(source).toContain('relatedPosts?: BlogContent[];');
+    expect(source).toContain('authors: MicroCMSContentId[];');
+  });
+
+  it('全フィールドタイプの型マッピングを正しく生成する', () => {
+    const source = renderDefinitionsFile([
+      createTarget('full-test', {
+        apiType: 'LIST',
+        schema: createSchema({
+          apiFields: [
+            { fieldId: 'title', kind: 'text', required: true, multipleSelect: false },
+            { fieldId: 'body', kind: 'textArea', required: false, multipleSelect: false },
+            { fieldId: 'content', kind: 'richEditor', required: false, multipleSelect: false },
+            { fieldId: 'contentV2', kind: 'richEditorV2', required: false, multipleSelect: false },
+            { fieldId: 'contentOld', kind: 'richEditorOld', required: false, multipleSelect: false },
+            { fieldId: 'publishDate', kind: 'date', required: false, multipleSelect: false },
+            { fieldId: 'order', kind: 'number', required: false, multipleSelect: false },
+            { fieldId: 'isPublished', kind: 'boolean', required: true, multipleSelect: false },
+            { fieldId: 'thumbnail', kind: 'media', required: false, multipleSelect: false },
+            { fieldId: 'gallery', kind: 'mediaList', required: false, multipleSelect: false },
+            { fieldId: 'document', kind: 'file', required: false, multipleSelect: false },
+            {
+              fieldId: 'category',
+              kind: 'relation',
+              required: false,
+              multipleSelect: false,
+              referencedApiEndpoint: 'categories',
+            },
+            {
+              fieldId: 'relatedPosts',
+              kind: 'relationList',
+              required: false,
+              multipleSelect: false,
+              referencedApiEndpoint: 'blog',
+            },
+            {
+              fieldId: 'status',
+              kind: 'select',
+              required: true,
+              multipleSelect: false,
+              selectItems: ['draft', 'published', 'archived'],
+            },
+            { fieldId: 'tags', kind: 'select', required: false, multipleSelect: true },
+            { fieldId: 'widget', kind: 'iframe', required: false, multipleSelect: false },
+            { fieldId: 'plugin', kind: 'extension', required: false, multipleSelect: false },
+            {
+              fieldId: 'hero',
+              kind: 'custom',
+              required: false,
+              multipleSelect: false,
+              customFieldCreatedAt: 'cf-hero',
+            },
+            {
+              fieldId: 'sections',
+              kind: 'repeater',
+              required: false,
+              multipleSelect: false,
+              customFieldCreatedAtList: ['cf-text-block', 'cf-image-block'],
+            },
+            {
+              fieldId: 'orphanRelation',
+              kind: 'relation',
+              required: false,
+              multipleSelect: false,
+            },
+            {
+              fieldId: 'orphanRelationList',
+              kind: 'relationList',
+              required: false,
+              multipleSelect: false,
+            },
+            { fieldId: 'unknownKind', kind: 'futureType', required: false, multipleSelect: false },
+          ],
+          customFields: [
+            {
+              createdAt: 'cf-hero',
+              fieldId: 'hero-banner',
+              fields: [
+                { fieldId: 'image', kind: 'media', required: true, multipleSelect: false },
+                { fieldId: 'caption', kind: 'text', required: false, multipleSelect: false },
+              ],
+            },
+            {
+              createdAt: 'cf-text-block',
+              fieldId: 'text-block',
+              fields: [
+                { fieldId: 'heading', kind: 'text', required: true, multipleSelect: false },
+                { fieldId: 'paragraph', kind: 'richEditor', required: false, multipleSelect: false },
+              ],
+            },
+            {
+              createdAt: 'cf-image-block',
+              fieldId: 'image-block',
+              fields: [
+                { fieldId: 'image', kind: 'media', required: true, multipleSelect: false },
+                { fieldId: 'alt', kind: 'text', required: false, multipleSelect: false },
+              ],
+            },
+          ],
+        }),
+      }),
+    ]);
+
+    // text → string
+    expect(source).toContain('title: string;');
+    // textArea → string (optional)
+    expect(source).toContain('body?: string;');
+    // richEditor → string
+    expect(source).toContain('content?: string;');
+    // richEditorV2 → string
+    expect(source).toContain('contentV2?: string;');
+    // richEditorOld → string
+    expect(source).toContain('contentOld?: string;');
+    // date → string
+    expect(source).toContain('publishDate?: string;');
+    // number → number
+    expect(source).toContain('order?: number;');
+    // boolean → boolean
+    expect(source).toContain('isPublished: boolean;');
+    // media → MicroCMSImage
+    expect(source).toContain('thumbnail?: MicroCMSImage;');
+    // mediaList → MicroCMSImage[]
+    expect(source).toContain('gallery?: MicroCMSImage[];');
+    // file → MicroCMSFile
+    expect(source).toContain('document?: MicroCMSFile;');
+    // relation (with endpoint) → XxxContent | null
+    expect(source).toContain('category?: CategoriesContent | null;');
+    // relationList (with endpoint) → XxxContent[]
+    expect(source).toContain('relatedPosts?: BlogContent[];');
+    // select (with selectItems) → literal union array
+    expect(source).toContain('status: ("draft" | "published" | "archived")[];');
+    // select (without selectItems) → string[]
+    expect(source).toContain('tags?: string[];');
+    // iframe → Record<string, unknown>
+    expect(source).toContain('widget?: Record<string, unknown>;');
+    // extension → Record<string, unknown>
+    expect(source).toContain('plugin?: Record<string, unknown>;');
+    // custom → custom type
+    expect(source).toContain('hero?: FullTestHeroBannerCustomField;');
+    // repeater → Array<union of custom types>
+    expect(source).toMatch(/sections\?: Array<.*TextBlock.*ImageBlock/);
+    // relation (without endpoint) → MicroCMSContentId | null
+    expect(source).toContain('orphanRelation?: MicroCMSContentId | null;');
+    // relationList (without endpoint) → MicroCMSContentId[]
+    expect(source).toContain('orphanRelationList?: MicroCMSContentId[];');
+    // unknown kind → unknown
+    expect(source).toContain('unknownKind?: unknown;');
+
+    // custom field types
+    expect(source).toContain('export type FullTestHeroBannerCustomField = {');
+    expect(source).toContain('export type FullTestTextBlockCustomField = {');
+    expect(source).toContain('export type FullTestImageBlockCustomField = {');
+
+    // LIST API generates ListResponse
+    expect(source).toContain(
+      'export type FullTestListResponse = MicroCMSListResponse<FullTestSchema>;',
+    );
+    // LIST API uses MicroCMSListContent
+    expect(source).toContain(
+      'export type FullTestContent = FullTestSchema & MicroCMSListContent;',
+    );
+  });
+
+  it('共通型が microcms-js-sdk の型定義と一致する', () => {
+    const source = renderDefinitionsFile([createTarget('dummy', { apiType: 'LIST' })]);
+
+    // MicroCMSContentId
+    expect(source).toContain('export interface MicroCMSContentId {');
+    expect(source).toContain('  id: string;');
+
+    // MicroCMSDate
+    expect(source).toContain('export interface MicroCMSDate {');
+    expect(source).toContain('  createdAt: string;');
+    expect(source).toContain('  updatedAt: string;');
+    expect(source).toContain('  publishedAt?: string;');
+    expect(source).toContain('  revisedAt?: string;');
+
+    // MicroCMSImage
+    expect(source).toContain('export interface MicroCMSImage {');
+    expect(source).toContain('  url: string;');
+    expect(source).toContain('  width?: number;');
+    expect(source).toContain('  height?: number;');
+    expect(source).toContain('  alt?: string;');
+
+    // MicroCMSListResponse
+    expect(source).toContain('export interface MicroCMSListResponse<T> {');
+    expect(source).toContain('  contents: (T & MicroCMSListContent)[];');
+    expect(source).toContain('  totalCount: number;');
+    expect(source).toContain('  limit: number;');
+    expect(source).toContain('  offset: number;');
+
+    // MicroCMSListContent / MicroCMSObjectContent
+    expect(source).toContain(
+      'export type MicroCMSListContent = MicroCMSContentId & MicroCMSDate;',
+    );
+    expect(source).toContain('export type MicroCMSObjectContent = MicroCMSDate;');
+  });
+
   it('custom/repeater の不正・未知データを安全にフォールバックして型生成する', () => {
     const source = renderDefinitionsFile([
       createTarget('page', {
diff --git a/src/commands/generate/types/management-api.ts b/src/commands/generate/types/management-api.ts
index 88a91d1..1ef53e6 100644
--- a/src/commands/generate/types/management-api.ts
+++ b/src/commands/generate/types/management-api.ts
@@ -40,6 +40,26 @@ async function fetchFromManagementApi(url: string, apiKey: string): Promise<unkn
   return response.json();
 }
 
+function parseSelectItems(rawItems: unknown): string[] | undefined {
+  if (!Array.isArray(rawItems) || rawItems.length === 0) {
+    return undefined;
+  }
+
+  const values = rawItems
+    .map((item) => {
+      if (typeof item === 'string') {
+        return item;
+      }
+      if (isRecord(item) && typeof item.value === 'string') {
+        return item.value;
+      }
+      return undefined;
+    })
+    .filter((item): item is string => item !== undefined);
+
+  return values.length > 0 ? values : undefined;
+}
+
 function parseApiField(rawField: unknown): ManagementApiField | null {
   if (!isRecord(rawField)) {
     return null;
@@ -59,6 +79,7 @@ function parseApiField(rawField: unknown): ManagementApiField | null {
     referencedApiEndpoint: toStringValue(rawField.referencedApiEndpoint),
     customFieldCreatedAt: toStringValue(rawField.customFieldCreatedAt),
     customFieldCreatedAtList: toStringArray(rawField.customFieldCreatedAtList),
+    selectItems: parseSelectItems(rawField.selectItems),
   };
 }
 
diff --git a/src/commands/generate/types/type-generator.ts b/src/commands/generate/types/type-generator.ts
index 87ced8f..27827ab 100644
--- a/src/commands/generate/types/type-generator.ts
+++ b/src/commands/generate/types/type-generator.ts
@@ -106,14 +106,23 @@ function resolveFieldType(field: ManagementApiField, context: GenerationContext)
       return 'MicroCMSImage[]';
     case 'file':
       return 'MicroCMSFile';
-    case 'relation':
-      return field.referencedApiEndpoint
+    case 'relation': {
+      const refType = field.referencedApiEndpoint
         ? `${toPascalCase(field.referencedApiEndpoint)}Content`
         : 'MicroCMSContentId';
+      return `${refType} | null`;
+    }
     case 'relationList':
-      return 'MicroCMSContentId[]';
-    case 'select':
-      return field.multipleSelect ? 'string[]' : 'string';
+      return field.referencedApiEndpoint
+        ? `${toPascalCase(field.referencedApiEndpoint)}Content[]`
+        : 'MicroCMSContentId[]';
+    case 'select': {
+      if (field.selectItems && field.selectItems.length > 0) {
+        const union = field.selectItems.map((item) => JSON.stringify(item)).join(' | ');
+        return `(${union})[]`;
+      }
+      return 'string[]';
+    }
     case 'iframe':
     case 'extension':
       return 'Record<string, unknown>';
diff --git a/src/commands/generate/types/types.ts b/src/commands/generate/types/types.ts
index 17f824b..20b1c3c 100644
--- a/src/commands/generate/types/types.ts
+++ b/src/commands/generate/types/types.ts
@@ -24,6 +24,7 @@ export interface ManagementApiField {
   referencedApiEndpoint?: string;
   customFieldCreatedAt?: string;
   customFieldCreatedAtList?: string[];
+  selectItems?: string[];
 }
 
 export interface ManagementCustomField {