Abstract: The implementation of regional environmental policies is of great significance for improving environmental quality and promoting the construction of ecological civilization. Based on the perspective of inter-governmental relations,the analysis of government behavior in the process of regional environmental policy implementation by constructing a game model reveals that in the process of regional environmental policy implementation,there is "collusion behavior" between horizontal inter-governmental governments,and negative "collusion behavior" will lead to deviations in policy implementation; there is a policy implementation mechanism for administrative contracting between the central and local governments. Under the political championship centered on economic growth,it will result in a "prisoner's dilemma" for policy implementation; In terms of dimensions,the central government's regulatory measures are necessary to constrain the implementation bias of local government policies. To this end,local governments should enhance mutual trust and information sharing; the central government must improve the policy implementation mechanism,performance evaluation mechanism,incentive mechanism,accountability mechanism and coordination mechanism; establish a social supervision system; and promote technological innovation in regional environmental governance.