diff --git a/pymbolic/interop/sympy.py b/pymbolic/interop/sympy.py
index bbea0991df97a47fcd08b1036d9a6f6aa2980a43..2f538a7858eb0ef10d8610e2ea705f5c6cdd35fe 100644
--- a/pymbolic/interop/sympy.py
+++ b/pymbolic/interop/sympy.py
@@ -56,6 +56,10 @@ class SympyToPymbolicMapper(SympyLikeToPymbolicMapper):
     def function_name(self, expr):
         return type(expr).__name__
 
+    # only called for Py2
+    def map_long(self, expr):
+        return long(expr)  # noqa
+
 # }}}
 
 
diff --git a/test/test_pymbolic.py b/test/test_pymbolic.py
index 98364588c7a9367cf9129726d12f16eeab29160c..95182c741f8479884d7b9af9b5d70bf9bd6783be 100644
--- a/test/test_pymbolic.py
+++ b/test/test_pymbolic.py
@@ -480,6 +480,13 @@ def test_unifier():
     assert match_found(recs, set([(a, b), (b, c), (c, d)]))
 
 
+def test_long_sympy_mapping():
+    from pymbolic.interop.sympy import SympyToPymbolicMapper
+    import sympy as sp
+    SympyToPymbolicMapper()(sp.sympify(int(10**20)))
+    SympyToPymbolicMapper()(sp.sympify(int(10)))
+
+
 if __name__ == "__main__":
     import sys
     if len(sys.argv) > 1: