diff --git a/pymbolic/interop/sympy.py b/pymbolic/interop/sympy.py
index 016733872ef55c41f6273cb75df0f1c0837b03e2..034fb9c5aea314998ff33fb9e17c219c4b11591e 100644
--- a/pymbolic/interop/sympy.py
+++ b/pymbolic/interop/sympy.py
@@ -85,6 +85,10 @@ class SympyToPymbolicMapper(SympyMapper):
     def map_ImaginaryUnit(self, expr):  # noqa
         return 1j
 
+    # only called for Py2
+    def map_long(self, expr):
+        return long(expr)  # noqa
+
     def map_Float(self, expr):  # noqa
         return float(expr)
 
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: