diff --git a/src/System.Management.Automation/FormatAndOutput/common/PSStyle.cs b/src/System.Management.Automation/FormatAndOutput/common/PSStyle.cs
index 3f927afd7d5..534f9541195 100644
--- a/src/System.Management.Automation/FormatAndOutput/common/PSStyle.cs
+++ b/src/System.Management.Automation/FormatAndOutput/common/PSStyle.cs
@@ -892,7 +892,7 @@ public static string MapColorPairToEscapeSequence(ConsoleColor foregroundColor,
                 throw new ArgumentOutOfRangeException(paramName: nameof(foregroundColor));
             }
 
-            if (backIndex < 0 || backIndex >= ForegroundColorMap.Length)
+            if (backIndex < 0 || backIndex >= BackgroundColorMap.Length)
             {
                 throw new ArgumentOutOfRangeException(paramName: nameof(backgroundColor));
             }