diff --git a/src/components/chart/element/element.heatmap.js b/src/components/chart/element/element.heatmap.js
index 00fa46ab0..2acef1dc8 100644
--- a/src/components/chart/element/element.heatmap.js
+++ b/src/components/chart/element/element.heatmap.js
@@ -108,7 +108,7 @@ class HeatMap {
     const xsp = chartRect.x1 + labelOffset.left;
     const ysp = chartRect.y2 - labelOffset.bottom;
 
-    this.size.w = Math.ceil(xArea / (this.spaces.x || (minmaxX.graphMax - minmaxX.graphMin)));
+    this.size.w = Math.floor(xArea / (this.spaces.x || (minmaxX.graphMax - minmaxX.graphMin)));
     this.size.h = Math.floor(yArea / (this.spaces.y || (minmaxY.graphMax - minmaxY.graphMin)));
 
     this.data.forEach((item) => {
diff --git a/src/components/chart/model/model.store.js b/src/components/chart/model/model.store.js
index a268b8346..8e1a78e48 100644
--- a/src/components/chart/model/model.store.js
+++ b/src/components/chart/model/model.store.js
@@ -441,7 +441,7 @@ const modules = {
 
     if (!opt.startToZero || targetMin > 0) {
       const targetSpace = space ? (space - 1) : (targetMax - targetMin);
-      const targetStep = targetInterval || Math.ceil((max - targetMin) / targetSpace);
+      const targetStep = Math.ceil((max - targetMin) / targetSpace);
         targetMin = targetMin < targetStep ? 0 : targetMin - targetStep;
     }