diff --git a/Runtime/Component/Sub/AxisLabel.cs b/Runtime/Component/Sub/AxisLabel.cs
index e45bee3f..1751f4dc 100644
--- a/Runtime/Component/Sub/AxisLabel.cs
+++ b/Runtime/Component/Sub/AxisLabel.cs
@@ -131,7 +131,7 @@ namespace XCharts
                 m_FontSize == other.fontSize &&
                 m_FontStyle == other.fontStyle &&
                 m_ForceENotation == other.forceENotation &&
-                m_Formatter.Equals(other.formatter) &&
+                ChartHelper.IsValueEqualsString(m_Formatter, other.formatter) &&
                 m_TextLimit.Equals(other.textLimit);
         }
 
@@ -142,7 +142,7 @@ namespace XCharts
 
         public void SetRelatedText(Text txt, float labelWidth)
         {
-            m_TextLimit.SetRelatedText(txt,labelWidth);
+            m_TextLimit.SetRelatedText(txt, labelWidth);
         }
 
         public string GetFormatterContent(string category)
diff --git a/Runtime/Utility/ChartHelper.cs b/Runtime/Utility/ChartHelper.cs
index 091260c5..c123814a 100644
--- a/Runtime/Utility/ChartHelper.cs
+++ b/Runtime/Utility/ChartHelper.cs
@@ -370,6 +370,13 @@ namespace XCharts
                 color1.r == color2.r;
         }
 
+        public static bool IsValueEqualsString(string str1, string str2)
+        {
+            if (str1 == null && str2 == null) return true;
+            else if (str1 != null && str2 != null) return str1.Equals(str2);
+            else return false;
+        }
+
         public static bool IsValueEqualsVector2(Vector2 v1, Vector2 v2)
         {
             return v1.x == v2.x && v1.y == v2.y;