diff --git a/packages/mermaid/src/themes/theme-base.js b/packages/mermaid/src/themes/theme-base.js
index 1f858275f..73ffef070 100644
--- a/packages/mermaid/src/themes/theme-base.js
+++ b/packages/mermaid/src/themes/theme-base.js
@@ -230,6 +230,20 @@ class Theme {
     this.pieOuterStrokeColor = this.pieOuterStrokeColor || 'black';
     this.pieOpacity = this.pieOpacity || '0.7';
 
+    /* radar */
+    this.radar = {
+      axisColor: this.radar?.axisColor || this.lineColor,
+      axisStrokeWidth: this.radar?.axisStrokeWidth || 2,
+      axisLabelFontSize: this.radar?.axisLabelFontSize || 12,
+      curveOpacity: this.radar?.curveOpacity || 0.5,
+      curveStrokeWidth: this.radar?.curveStrokeWidth || 2,
+      graticuleColor: this.radar?.graticuleColor || '#DEDEDE',
+      graticuleStrokeWidth: this.radar?.graticuleStrokeWidth || 1,
+      graticuleOpacity: this.radar?.graticuleOpacity || 0.3,
+      legendBoxSize: this.radar?.legendBoxSize || 12,
+      legendFontSize: this.radar?.legendFontSize || 12,
+    };
+
     /* architecture */
     this.archEdgeColor = this.archEdgeColor || '#777';
     this.archEdgeArrowColor = this.archEdgeArrowColor || '#777';
diff --git a/packages/mermaid/src/themes/theme-dark.js b/packages/mermaid/src/themes/theme-dark.js
index a0df8d4f3..c452eea9f 100644
--- a/packages/mermaid/src/themes/theme-dark.js
+++ b/packages/mermaid/src/themes/theme-dark.js
@@ -291,6 +291,20 @@ class Theme {
       blockFillColor: this.background,
     };
 
+    /* radar */
+    this.radar = {
+      axisColor: this.radar?.axisColor || this.lineColor,
+      axisStrokeWidth: this.radar?.axisStrokeWidth || 2,
+      axisLabelFontSize: this.radar?.axisLabelFontSize || 12,
+      curveOpacity: this.radar?.curveOpacity || 0.5,
+      curveStrokeWidth: this.radar?.curveStrokeWidth || 2,
+      graticuleColor: this.radar?.graticuleColor || '#DEDEDE',
+      graticuleStrokeWidth: this.radar?.graticuleStrokeWidth || 1,
+      graticuleOpacity: this.radar?.graticuleOpacity || 0.3,
+      legendBoxSize: this.radar?.legendBoxSize || 12,
+      legendFontSize: this.radar?.legendFontSize || 12,
+    };
+
     /* class */
     this.classText = this.primaryTextColor;
 
diff --git a/packages/mermaid/src/themes/theme-default.js b/packages/mermaid/src/themes/theme-default.js
index 78f20a475..eba3ff101 100644
--- a/packages/mermaid/src/themes/theme-default.js
+++ b/packages/mermaid/src/themes/theme-default.js
@@ -291,6 +291,20 @@ class Theme {
       this.quadrantExternalBorderStrokeFill || this.primaryBorderColor;
     this.quadrantTitleFill = this.quadrantTitleFill || this.primaryTextColor;
 
+    /* radar */
+    this.radar = {
+      axisColor: this.radar?.axisColor || this.lineColor,
+      axisStrokeWidth: this.radar?.axisStrokeWidth || 2,
+      axisLabelFontSize: this.radar?.axisLabelFontSize || 12,
+      curveOpacity: this.radar?.curveOpacity || 0.5,
+      curveStrokeWidth: this.radar?.curveStrokeWidth || 2,
+      graticuleColor: this.radar?.graticuleColor || '#DEDEDE',
+      graticuleStrokeWidth: this.radar?.graticuleStrokeWidth || 1,
+      graticuleOpacity: this.radar?.graticuleOpacity || 0.3,
+      legendBoxSize: this.radar?.legendBoxSize || 12,
+      legendFontSize: this.radar?.legendFontSize || 12,
+    };
+
     /* xychart */
     this.xyChart = {
       backgroundColor: this.xyChart?.backgroundColor || this.background,
diff --git a/packages/mermaid/src/themes/theme-forest.js b/packages/mermaid/src/themes/theme-forest.js
index 34d965201..853b4d032 100644
--- a/packages/mermaid/src/themes/theme-forest.js
+++ b/packages/mermaid/src/themes/theme-forest.js
@@ -265,6 +265,20 @@ class Theme {
       blockFillColor: this.mainBkg,
     };
 
+    /* radar */
+    this.radar = {
+      axisColor: this.radar?.axisColor || this.lineColor,
+      axisStrokeWidth: this.radar?.axisStrokeWidth || 2,
+      axisLabelFontSize: this.radar?.axisLabelFontSize || 12,
+      curveOpacity: this.radar?.curveOpacity || 0.5,
+      curveStrokeWidth: this.radar?.curveStrokeWidth || 2,
+      graticuleColor: this.radar?.graticuleColor || '#DEDEDE',
+      graticuleStrokeWidth: this.radar?.graticuleStrokeWidth || 1,
+      graticuleOpacity: this.radar?.graticuleOpacity || 0.3,
+      legendBoxSize: this.radar?.legendBoxSize || 12,
+      legendFontSize: this.radar?.legendFontSize || 12,
+    };
+
     /* xychart */
     this.xyChart = {
       backgroundColor: this.xyChart?.backgroundColor || this.background,
diff --git a/packages/mermaid/src/themes/theme-neutral.js b/packages/mermaid/src/themes/theme-neutral.js
index 8b7f34ed8..633a26849 100644
--- a/packages/mermaid/src/themes/theme-neutral.js
+++ b/packages/mermaid/src/themes/theme-neutral.js
@@ -303,6 +303,20 @@ class Theme {
         '#EEE,#6BB8E4,#8ACB88,#C7ACD6,#E8DCC2,#FFB2A8,#FFF380,#7E8D91,#FFD8B1,#FAF3E0',
     };
 
+    /* radar */
+    this.radar = {
+      axisColor: this.radar?.axisColor || this.lineColor,
+      axisStrokeWidth: this.radar?.axisStrokeWidth || 2,
+      axisLabelFontSize: this.radar?.axisLabelFontSize || 12,
+      curveOpacity: this.radar?.curveOpacity || 0.5,
+      curveStrokeWidth: this.radar?.curveStrokeWidth || 2,
+      graticuleColor: this.radar?.graticuleColor || '#DEDEDE',
+      graticuleStrokeWidth: this.radar?.graticuleStrokeWidth || 1,
+      graticuleOpacity: this.radar?.graticuleOpacity || 0.3,
+      legendBoxSize: this.radar?.legendBoxSize || 12,
+      legendFontSize: this.radar?.legendFontSize || 12,
+    };
+
     /* requirement-diagram */
     this.requirementBackground = this.requirementBackground || this.primaryColor;
     this.requirementBorderColor = this.requirementBorderColor || this.primaryBorderColor;