diff --git a/packages/mermaid/src/rendering-util/rendering-elements/shapes/triangle.ts b/packages/mermaid/src/rendering-util/rendering-elements/shapes/triangle.ts
index fdb149023..ca35c2c70 100644
--- a/packages/mermaid/src/rendering-util/rendering-elements/shapes/triangle.ts
+++ b/packages/mermaid/src/rendering-util/rendering-elements/shapes/triangle.ts
@@ -8,15 +8,31 @@ import { createPathFromPoints } from './util.js';
 import { evaluate } from '../../../diagrams/common/common.js';
 import { getConfig } from '../../../diagram-api/diagramAPI.js';
 
+const MIN_HEIGHT = 25;
+const MIN_WIDTH = 25;
+
 export const triangle = async (parent: SVGAElement, node: Node): Promise<SVGAElement> => {
   const { labelStyles, nodeStyles } = styles2String(node);
   node.labelStyle = labelStyles;
+  const nodePadding = node.padding ?? 0;
+  const labelPaddingX = node.look === 'neo' ? nodePadding * 2 : nodePadding;
+
+  if (node.width || node.height) {
+    node.width = (node?.width ?? 0) - labelPaddingX * 4;
+    if (node.width < MIN_WIDTH) {
+      node.width = MIN_WIDTH;
+    }
+
+    node.height = node?.height ?? 0;
+    if (node.height < MIN_HEIGHT) {
+      node.height = MIN_HEIGHT;
+    }
+  }
+
   const { shapeSvg, bbox, label } = await labelHelper(parent, node, getNodeClasses(node));
   const useHtmlLabels = evaluate(getConfig().flowchart?.htmlLabels);
 
-  const nodePadding = node.padding ?? 0;
-  const labelPaddingX = node.look === 'neo' ? nodePadding * 2 : nodePadding;
-  const w = Math.max(bbox.width + (labelPaddingX ?? 0), node?.width ?? 0);
+  const w = Math.max(bbox.width, node?.width ?? 0) + labelPaddingX;
   const h = Math.max(w + bbox.height, node?.height ?? 0);
 
   const tw = w + bbox.height;