diff --git a/python/pyspark/rdd.py b/python/pyspark/rdd.py
index 1ed098c076ae5..4f9c928a57d97 100644
--- a/python/pyspark/rdd.py
+++ b/python/pyspark/rdd.py
@@ -28,7 +28,7 @@
 import socket
 from subprocess import Popen, PIPE
 from tempfile import NamedTemporaryFile
-from threading import Thread
+from threading import Thread, Lock
 from collections import defaultdict
 from itertools import chain
 from functools import reduce
@@ -57,6 +57,9 @@
 
 __all__ = ["RDD"]
 
+# Lock which will make sure that dependend broadcast variables are pickled along
+# with their PythonRDD wrapped function when using multple threads(SPARK-12717).
+_lock = Lock()
 
 def portable_hash(x):
     """
@@ -2374,14 +2377,15 @@ def _jrdd(self):
         else:
             profiler = None
 
-        command = (self.func, profiler, self._prev_jrdd_deserializer,
-                   self._jrdd_deserializer)
-        pickled_cmd, bvars, env, includes = _prepare_for_python_RDD(self.ctx, command, self)
-        python_rdd = self.ctx._jvm.PythonRDD(self._prev_jrdd.rdd(),
-                                             bytearray(pickled_cmd),
-                                             env, includes, self.preservesPartitioning,
-                                             self.ctx.pythonExec, self.ctx.pythonVer,
-                                             bvars, self.ctx._javaAccumulator)
+        with _lock:
+            command = (self.func, profiler, self._prev_jrdd_deserializer,
+                       self._jrdd_deserializer)
+            pickled_cmd, bvars, env, includes = _prepare_for_python_RDD(self.ctx, command, self)
+            python_rdd = self.ctx._jvm.PythonRDD(self._prev_jrdd.rdd(),
+                                                 bytearray(pickled_cmd),
+                                                 env, includes, self.preservesPartitioning,
+                                                 self.ctx.pythonExec, self.ctx.pythonVer,
+                                                 bvars, self.ctx._javaAccumulator)
         self._jrdd_val = python_rdd.asJavaRDD()
 
         if profiler: