diff --git a/doc/source/release.rst b/doc/source/release.rst
index 153b4c4f464be..d761f1f008754 100644
--- a/doc/source/release.rst
+++ b/doc/source/release.rst
@@ -184,6 +184,8 @@ pandas 0.13
   - Fix arithmetic with series/datetimeindex and ``np.timedelta64`` not working the same (:issue:`4134`)
     and buggy timedelta in numpy 1.6 (:issue:`4135`)
   - Fix bug in ``pd.read_clipboard`` on windows with PY3 (:issue:`4561`); not decoding properly
+  - ``tslib.get_period_field()`` and ``tslib.get_period_field_arr()`` now raise
+    if code argument out of range (:issue:`4519`, :issue:`4520`)
 
 pandas 0.12
 ===========
diff --git a/pandas/tests/test_tseries.py b/pandas/tests/test_tseries.py
index 1ed6dd4469f4d..6175b358a925c 100644
--- a/pandas/tests/test_tseries.py
+++ b/pandas/tests/test_tseries.py
@@ -700,6 +700,16 @@ def test_to_datetime_bijective(self):
         self.assertEqual(Timestamp(Timestamp.max.to_pydatetime()).value/1000, Timestamp.max.value/1000)
         self.assertEqual(Timestamp(Timestamp.min.to_pydatetime()).value/1000, Timestamp.min.value/1000)
 
+class TestPeriodField(unittest.TestCase):
+
+    def test_get_period_field_raises_on_out_of_range(self):
+        from pandas import tslib
+        self.assertRaises(ValueError, tslib.get_period_field, -1, 0, 0)
+
+    def test_get_period_field_array_raises_on_out_of_range(self):
+        from pandas import tslib
+        self.assertRaises(ValueError, tslib.get_period_field_arr, -1, np.empty(1), 0)
+
 if __name__ == '__main__':
     import nose
     nose.runmodule(argv=[__file__, '-vvs', '-x', '--pdb', '--pdb-failure'],
diff --git a/pandas/tslib.pyx b/pandas/tslib.pyx
index 698d9a81af387..18917fdd82d1b 100644
--- a/pandas/tslib.pyx
+++ b/pandas/tslib.pyx
@@ -2419,6 +2419,8 @@ ctypedef int (*accessor)(int64_t ordinal, int freq) except INT32_MIN
 
 def get_period_field(int code, int64_t value, int freq):
     cdef accessor f = _get_accessor_func(code)
+    if f is NULL:
+        raise ValueError('Unrecognized period code: %d' % code)
     return f(value, freq)
 
 def get_period_field_arr(int code, ndarray[int64_t] arr, int freq):
@@ -2428,6 +2430,8 @@ def get_period_field_arr(int code, ndarray[int64_t] arr, int freq):
         accessor f
 
     f = _get_accessor_func(code)
+    if f is NULL:
+        raise ValueError('Unrecognized period code: %d' % code)
 
     sz = len(arr)
     out = np.empty(sz, dtype=np.int64)
@@ -2462,8 +2466,7 @@ cdef accessor _get_accessor_func(int code):
         return &pday_of_year
     elif code == 10:
         return &pweekday
-    else:
-        raise ValueError('Unrecognized code: %s' % code)
+    return NULL
 
 
 def extract_ordinals(ndarray[object] values, freq):