diff --git a/amber/src/main/python/core/storage/iceberg/iceberg_catalog_instance.py b/amber/src/main/python/core/storage/iceberg/iceberg_catalog_instance.py
index 0059808f9f8..65a4f6beec3 100644
--- a/amber/src/main/python/core/storage/iceberg/iceberg_catalog_instance.py
+++ b/amber/src/main/python/core/storage/iceberg/iceberg_catalog_instance.py
@@ -60,10 +60,6 @@ def get_instance(cls):
                     "texera_iceberg",
                     StorageConfig.ICEBERG_REST_CATALOG_WAREHOUSE_NAME,
                     StorageConfig.ICEBERG_REST_CATALOG_URI,
-                    StorageConfig.S3_ENDPOINT,
-                    StorageConfig.S3_REGION,
-                    StorageConfig.S3_AUTH_USERNAME,
-                    StorageConfig.S3_AUTH_PASSWORD,
                 )
             else:
                 raise ValueError(f"Unsupported catalog type: {catalog_type}")
diff --git a/amber/src/main/python/core/storage/iceberg/iceberg_utils.py b/amber/src/main/python/core/storage/iceberg/iceberg_utils.py
index 844ef3e00ff..c66ba74ba27 100644
--- a/amber/src/main/python/core/storage/iceberg/iceberg_utils.py
+++ b/amber/src/main/python/core/storage/iceberg/iceberg_utils.py
@@ -157,23 +157,15 @@ def create_rest_catalog(
     catalog_name: str,
     warehouse_name: str,
     rest_uri: str,
-    s3_endpoint: str,
-    s3_region: str,
-    s3_username: str,
-    s3_password: str,
 ) -> Catalog:
     """
     Creates a REST catalog instance by connecting to a REST endpoint.
-    - Configures the catalog to interact with a REST endpoint.
     - The warehouse_name parameter specifies the warehouse identifier.
-    - Configures S3FileIO for MinIO/S3 storage backend.
+    - S3 settings (endpoint, region, credentials) are supplied by the REST
+      catalog server at runtime.
     :param catalog_name: the name of the catalog.
     :param warehouse_name: the warehouse identifier.
     :param rest_uri: the URI of the REST catalog endpoint.
-    :param s3_endpoint: the S3 endpoint URL.
-    :param s3_region: the S3 region.
-    :param s3_username: the S3 access key ID.
-    :param s3_password: the S3 secret access key.
     :return: a Catalog instance (REST catalog).
     """
     return load_catalog(
@@ -182,11 +174,6 @@ def create_rest_catalog(
             "type": "rest",
             "uri": rest_uri,
             "warehouse": warehouse_name,
-            "s3.endpoint": s3_endpoint,
-            "s3.access-key-id": s3_username,
-            "s3.secret-access-key": s3_password,
-            "s3.region": s3_region,
-            "s3.path-style-access": "true",
         },
     )
 
diff --git a/amber/src/test/python/core/storage/iceberg/test_iceberg_rest_catalog_integration.py b/amber/src/test/python/core/storage/iceberg/test_iceberg_rest_catalog_integration.py
index 642fbb08e52..f023bd70d5c 100644
--- a/amber/src/test/python/core/storage/iceberg/test_iceberg_rest_catalog_integration.py
+++ b/amber/src/test/python/core/storage/iceberg/test_iceberg_rest_catalog_integration.py
@@ -33,10 +33,6 @@ def rest_catalog():
         catalog_name="rest_integration_test",
         warehouse_name="texera",
         rest_uri="http://localhost:8181/catalog/",
-        s3_endpoint="http://localhost:9000",
-        s3_region="us-west-2",
-        s3_username="texera_minio",
-        s3_password="password",
     )
 
 
diff --git a/common/workflow-core/src/main/scala/org/apache/texera/amber/util/IcebergUtil.scala b/common/workflow-core/src/main/scala/org/apache/texera/amber/util/IcebergUtil.scala
index d6e406a53fc..cee293a7580 100644
--- a/common/workflow-core/src/main/scala/org/apache/texera/amber/util/IcebergUtil.scala
+++ b/common/workflow-core/src/main/scala/org/apache/texera/amber/util/IcebergUtil.scala
@@ -108,19 +108,12 @@ object IcebergUtil {
   ): RESTCatalog = {
     val catalog = new RESTCatalog()
 
-    // Build base properties map
-    var properties = Map(
+    // S3 settings (endpoint, region, credentials) are supplied by the REST
+    // catalog server at runtime.
+    val properties = Map(
       "warehouse" -> warehouse,
-      CatalogProperties.URI -> StorageConfig.icebergRESTCatalogUri
-    )
-
-    properties = properties ++ Map(
-      CatalogProperties.FILE_IO_IMPL -> classOf[S3FileIO].getName,
-      "s3.endpoint" -> StorageConfig.s3Endpoint,
-      "s3.access-key-id" -> StorageConfig.s3Username,
-      "s3.secret-access-key" -> StorageConfig.s3Password,
-      "s3.region" -> StorageConfig.s3Region,
-      "s3.path-style-access" -> "true"
+      CatalogProperties.URI -> StorageConfig.icebergRESTCatalogUri,
+      CatalogProperties.FILE_IO_IMPL -> classOf[S3FileIO].getName
     )
 
     catalog.initialize(catalogName, properties.asJava)
diff --git a/common/workflow-core/src/test/scala/org/apache/texera/amber/util/IcebergUtilSpec.scala b/common/workflow-core/src/test/scala/org/apache/texera/amber/util/IcebergUtilSpec.scala
index da15a8060d3..d81c00541ee 100644
--- a/common/workflow-core/src/test/scala/org/apache/texera/amber/util/IcebergUtilSpec.scala
+++ b/common/workflow-core/src/test/scala/org/apache/texera/amber/util/IcebergUtilSpec.scala
@@ -22,6 +22,7 @@ package org.apache.texera.amber.util
 import org.apache.texera.amber.core.tuple.{AttributeType, LargeBinary, Schema, Tuple}
 import org.apache.texera.amber.util.IcebergUtil.toIcebergSchema
 import org.apache.iceberg.data.GenericRecord
+import org.apache.iceberg.exceptions.RESTException
 import org.apache.iceberg.types.Types
 import org.apache.iceberg.{Schema => IcebergSchema}
 import org.scalatest.flatspec.AnyFlatSpec
@@ -298,4 +299,13 @@ class IcebergUtilSpec extends AnyFlatSpec {
 
     assert(IcebergUtil.fromRecord(record, schema) == tuple)
   }
+
+  it should "build REST catalog properties without S3 settings" in {
+    // Property Map is built before any network call. With or without
+    // Lakekeeper reachable, .initialize surfaces a RESTException — the
+    // failure is on the server side, not from Map composition.
+    intercept[RESTException] {
+      IcebergUtil.createRestCatalog("test", "non-existent-warehouse")
+    }
+  }
 }