diff --git a/src/processor/dataStack.ts b/src/processor/dataStack.ts
index f83c7f90f6..48ce66ec19 100644
--- a/src/processor/dataStack.ts
+++ b/src/processor/dataStack.ts
@@ -150,8 +150,9 @@ function calculateStack(stackInfoList: StackInfo[]) {
                         stackStrategy === 'all' // single stack group
                         || (stackStrategy === 'positive' && val > 0)
                         || (stackStrategy === 'negative' && val < 0)
-                        || (stackStrategy === 'samesign' && sum >= 0 && val > 0) // All positive stack
-                        || (stackStrategy === 'samesign' && sum <= 0 && val < 0) // All negative stack
+                        // For 'samesign', 0 is not stacked.
+                        || (stackStrategy === 'samesign' && sum > 0 && val > 0) // All positive stack
+                        || (stackStrategy === 'samesign' && sum < 0 && val < 0) // All negative stack
                     ) {
                         // The sum has to be very small to be affected by the
                         // floating arithmetic problem. An incorrect result will probably
diff --git a/test/ut/jest.config.cjs b/test/ut/jest.config.cjs
index 5ca8031953..0eac19b025 100644
--- a/test/ut/jest.config.cjs
+++ b/test/ut/jest.config.cjs
@@ -46,7 +46,8 @@ module.exports = {
         '**/spec/data/*.test.ts',
         '**/spec/model/*.test.ts',
         '**/spec/scale/*.test.ts',
-        '**/spec/util/*.test.ts'
+        '**/spec/util/*.test.ts',
+        '**/spec/processor/*.test.ts'
     ],
     moduleNameMapper: pathsToModuleNameMapper(compilerOptions.paths, {
         prefix: '<rootDir>/'
diff --git a/test/ut/spec/processor/dataStack.test.ts b/test/ut/spec/processor/dataStack.test.ts
new file mode 100644
index 0000000000..0730bd2437
--- /dev/null
+++ b/test/ut/spec/processor/dataStack.test.ts
@@ -0,0 +1,102 @@
+import { createChart, getECModel } from '../../core/utHelper';
+import { EChartsType } from '@/src/echarts.all';
+
+describe('processor/dataStack', function() {
+    let chart: EChartsType;
+    beforeEach(function () {
+        chart = createChart();
+    });
+
+    afterEach(function () {
+        chart.dispose();
+    });
+
+    it('should not stack on zero value with samesign strategy', function() {
+        chart.setOption({
+            xAxis: { data: ['a', 'b', 'c'] },
+            yAxis: { type: 'value' },
+            series: [{
+                type: 'line',
+                data: [10, 20, 30],
+                stack: 'total',
+                stackStrategy: 'samesign'
+            }, {
+                type: 'line',
+                data: [5, 0, 10],
+                stack: 'total',
+                stackStrategy: 'samesign'
+            }]
+        });
+
+        const ecModel = getECModel(chart);
+        const seriesModels = ecModel.getSeries();
+        const resultData = seriesModels[1].getData();
+        const stackResultDim = resultData.getCalculationInfo('stackResultDimension');
+        const stackedOverDim = resultData.getCalculationInfo('stackedOverDimension');
+
+        // with the fix, stackResultDimension at index 1 should be 0, and stackedOverDimension should be NaN
+        expect(resultData.get(stackResultDim, 1)).toEqual(0);
+        expect(resultData.get(stackedOverDim, 1)).toBeNaN();
+    });
+
+    it('should not stack on zero value when stacked on zero value', function() {
+        chart.setOption({
+            xAxis: { data: ['a', 'b', 'c'] },
+            yAxis: { type: 'value' },
+            series: [{
+                type: 'line',
+                data: [10, 0, 30],
+                stack: 'total',
+                stackStrategy: 'samesign'
+            }, {
+                type: 'line',
+                data: [5, 0, 10],
+                stack: 'total',
+                stackStrategy: 'samesign'
+            }]
+        });
+
+        const ecModel = getECModel(chart);
+        const seriesModels = ecModel.getSeries();
+        const resultData = seriesModels[1].getData();
+        const stackResultDim = resultData.getCalculationInfo('stackResultDimension');
+        const stackedOverDim = resultData.getCalculationInfo('stackedOverDimension');
+
+        expect(resultData.get(stackResultDim, 1)).toEqual(0);
+        expect(resultData.get(stackedOverDim, 1)).toBeNaN();
+    });
+
+    it('should correctly stack when a zero value series is in the middle', function() {
+        chart.setOption({
+            xAxis: { data: ['a', 'b', 'c'] },
+            yAxis: { type: 'value' },
+            series: [{
+                type: 'line',
+                data: [10, 20, 30],
+                stack: 'total',
+                stackStrategy: 'samesign'
+            }, {
+                type: 'line',
+                data: [5, 0, -10],
+                stack: 'total',
+                stackStrategy: 'samesign'
+            }, {
+                type: 'line',
+                data: [5, 5, 5],
+                stack: 'total',
+                stackStrategy: 'samesign'
+            }]
+        });
+
+        const ecModel = getECModel(chart);
+        const seriesModels = ecModel.getSeries();
+        const resultData = seriesModels[2].getData();
+        const stackResultDim = resultData.getCalculationInfo('stackResultDimension');
+        const stackedOverDim = resultData.getCalculationInfo('stackedOverDimension');
+
+        // series 3 should be stacked on series 1, because series 2 has a zero and a negative value.
+        expect(resultData.get(stackResultDim, 1)).toEqual(25);
+        expect(resultData.get(stackedOverDim, 1)).toEqual(20);
+    });
+});
+