diff --git a/DetectorDescription/RegressionTest/test/run_DDErrorReport.py b/DetectorDescription/RegressionTest/test/run_DDErrorReport.py
index 91473313fa29d..d15705de93dfc 100755
--- a/DetectorDescription/RegressionTest/test/run_DDErrorReport.py
+++ b/DetectorDescription/RegressionTest/test/run_DDErrorReport.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 import FWCore.ParameterSet.Config as cms
 import sys