Thus the conflict between police and civilian escalates and finally forms the situation of "government illegal land expropriation→farms struggle→government violating rules of dispatching police→conflict between po-lice and civilian".

According to the current situation of illegal land-use condition,this paper puts forward the opinion that there exist game practices among land supervisor,local government and land supervision department because of information asymmetry,and conceives a game model among them based on the assumption that they are rational and strive to maximize their interests.