diff --git a/extensions/typescript-language-features/src/features/signatureHelpProvider.ts b/extensions/typescript-language-features/src/features/signatureHelpProvider.ts
index f23de59d5d6..7787b49e98c 100644
--- a/extensions/typescript-language-features/src/features/signatureHelpProvider.ts
+++ b/extensions/typescript-language-features/src/features/signatureHelpProvider.ts
@@ -50,7 +50,7 @@ export default class TypeScriptSignatureHelpProvider implements SignatureHelpPro
 			item.parameters.forEach((p, i, a) => {
 				const parameter = new ParameterInformation(
 					Previewer.plain(p.displayParts),
-					Previewer.plain(p.documentation));
+					Previewer.markdownDocumentation(p.documentation, []));
 
 				signature.label += parameter.label;
 				signature.parameters.push(parameter);