diff --git a/scapy/asn1/mib.py b/scapy/asn1/mib.py
index bd29da91a5536c53b1ddd8e8be6e8099fa8ff365..c5396556ef46b288bd6b7ef7c686117788df265f 100644
--- a/scapy/asn1/mib.py
+++ b/scapy/asn1/mib.py
@@ -63,6 +63,8 @@ class MIBDict(DADict):
             s += '\t"%s" -> "%s" [label="%s"];\n' % (parent, o,remainder)
         s += "}\n"
         do_graph(s, **kargs)
+    def __len__(self):
+        return len(self.keys())
 
 
 def mib_register(ident, value, the_mib, unresolved):