diff --git a/lib/internal/test_runner/reporter/spec.js b/lib/internal/test_runner/reporter/spec.js
index 2092d22e3fe77f..e45351a79f560c 100644
--- a/lib/internal/test_runner/reporter/spec.js
+++ b/lib/internal/test_runner/reporter/spec.js
@@ -69,8 +69,10 @@ class SpecReporter extends Transform {
       case 'test:stderr':
       case 'test:stdout':
         return data.message;
-      case 'test:diagnostic':
-        return `${reporterColorMap[type]}${indent(data.nesting)}${reporterUnicodeSymbolMap[type]}${data.message}${colors.white}\n`;
+      case 'test:diagnostic':{
+        const diagnosticColor = reporterColorMap[data.level] || reporterColorMap['test:diagnostic'];
+        return `${diagnosticColor}${indent(data.nesting)}${reporterUnicodeSymbolMap[type]}${data.message}${colors.white}\n`;
+      }
       case 'test:coverage':
         return getCoverageReport(indent(data.nesting), data.summary,
                                  reporterUnicodeSymbolMap['test:coverage'], colors.blue, true);