diff --git a/ocaml/xenopsd/scripts/igmp_query_injector.py b/ocaml/xenopsd/scripts/igmp_query_injector.py
index 1c2f533c1f8..59324b5526b 100755
--- a/ocaml/xenopsd/scripts/igmp_query_injector.py
+++ b/ocaml/xenopsd/scripts/igmp_query_injector.py
@@ -53,7 +53,8 @@ def inject_packet(self, iface, dst_mac):
         ether_part = Ether(src='00:00:00:00:00:00', dst=dst_mac)
         ip_part = IP(ttl=1, src='0.0.0.0', dst='224.0.0.1')
         igmp_part = IGMP(type=0x11)
-        igmp_part.mrcode = (self.max_resp_time / 100) & 0xff
+        # Should use integer division // in python 3
+        igmp_part.mrcode = (self.max_resp_time // 100) & 0xff
         igmp_part.igmpize()
         # Make this IGMP query packet as an unicast packet
         ether_part.dst = dst_mac