pyderasn.py            | 2 +-
 tests/test_pyderasn.py | 6 +++---

diff --git a/pyderasn.py b/pyderasn.py
index 8e5bd83e4101b30c82515672312a2cec988a0fb6b2ce0a9d6eec48c31cd388f9..9e04dc67a7b94aaf1ea9b076877d13f024150a7d8e262019bf2235d543ae99ce 100755
--- a/pyderasn.py
+++ b/pyderasn.py
@@ -3497,7 +3497,7 @@     __slots__ = ()
     tag_default = tag_encode(18)
     encoding = "ascii"
     asn1_type_name = "NumericString"
-    allowable_chars = set(digits.encode("ascii"))
+    allowable_chars = set(digits.encode("ascii") + b" ")
 
     def _value_sanitize(self, value):
         value = super(NumericString, self)._value_sanitize(value)
diff --git a/tests/test_pyderasn.py b/tests/test_pyderasn.py
index bfece03e6071b553877b02b2967bd1a1e69ceacec58affe6238d27e8f87ab428..6f023d05f607b10f44dc2f86cfc05a6b52fb1013d40e3ae1a22b8b6e7e9d458d 100644
--- a/tests/test_pyderasn.py
+++ b/tests/test_pyderasn.py
@@ -3296,12 +3296,12 @@ class TestNumericString(StringMixin, CommonMixin, TestCase):
     base_klass = NumericString
 
     def text_alphabet(self):
-        return digits
+        return digits + " "
 
     @given(text(alphabet=ascii_letters, min_size=1, max_size=5))
-    def test_non_numeric(self, cyrillic_text):
+    def test_non_numeric(self, non_numeric_text):
         with assertRaisesRegex(self, DecodeError, "non-numeric"):
-            self.base_klass(cyrillic_text)
+            self.base_klass(non_numeric_text)
 
     @given(
         sets(integers(min_value=0, max_value=10), min_size=2, max_size=2),