diff --git a/python/src/main/java/org/apache/zeppelin/python/PythonInterpreter.java b/python/src/main/java/org/apache/zeppelin/python/PythonInterpreter.java
index 4d8a4b726a2..e4ea7321672 100644
--- a/python/src/main/java/org/apache/zeppelin/python/PythonInterpreter.java
+++ b/python/src/main/java/org/apache/zeppelin/python/PythonInterpreter.java
@@ -219,7 +219,7 @@ private void appendToPythonPath(Map<String, String> env, String path) {
     if (!env.containsKey("PYTHONPATH")) {
       env.put("PYTHONPATH", path);
     } else {
-      env.put("PYTHONPATH", env.get("PYTHONPATH") + ":" + path);
+      env.put("PYTHONPATH", env.get("PYTHONPATH") + File.pathSeparator + path);
     }
   }