With　the　increase　of　global　malicious　activities,　it　is　particularly　necessary　to　optimize　the　allocation　of　limited　urban　protective　resources　and　protect　power　network　from　malicious　attacks.　There　is　plenty　of　research　on　evaluating　the　risks　of　malicious　attacks　on　electricity　network,　however,　conventional　risk-based　approach　does　not　take　strategic　adjustment　of　malicious　into　account,　nor　can　it　determine　the　optimal　allocation　of　global　protective　resources.　In　this　paper,　an　optimal　allocation　of　protective　resources　based　on　game　theory　was　proposed,　which　combined　game　theory　with　risk　assessment,　taking　full　account　of　strategic　interaction　between　defender　and　attacker.　IEEE　30-bus　network　was　taken　as　an　example　to　verify　the　applicability　and　reliability　of　the　method,　so　as　to　confirm　the　advantages　of　the　method　in　determining　the　global　optimal　allocation　of　protective　resources.　©　Published　under　licence　by　IOP　Publishing　Ltd.