In this paper，the author chooses health insurance reform in B City as a case to analysis the cross-sectoral policy implementation process. Health insurance cross-sectoral policy implementation in B City has gone a process of change from conflict，compromise to cooperation.The article analyses how the interactions between different organizations in the policy process affect the policy itself and the policy goals. The article also analysis the main factors leading to this process of change：conflicts of interest，the power constraints between different sectors，equal consultations and cross-sectoral coordination of interests. The article further develops a analysis model of cross-sectoral consultation policy implementation，and it is compared with the existing western policy implementation theories.