Based on the perspective of new structural economics, this paper makes a theoretical analysis of the relationship between development strategy and environmental governance, identifies its main mechanisms, namely the viability mechanism and the fiscal deficit mechanism, and then proposes research hypotheses. And based on the provincial panel data from 1997 to 2016, the paper conducts an empirical test on the relationship between them and its mechanisms.

The research finds that: （1） The more the region’s development strategy violates the comparative advantage, the weaker its environmental governance level will be. This conclusion is effectively identified after selecting " the shortest distance from threatened areas” and " the number of old industrial bases” as exogenous instrumental variables of development strategy. （2） From the sub-indicators of environmental governance, there are differences in the impact of development strategy on all dimensions of environmental governance. In contrast, the development strategy has less impact on the number of local environmental laws and administrative rules and regulations, and more impact on sewage fees, the number of administrative penalties, the number of environmental protection personnel, the total investment in environmental governance and the structure of environmental governance. This difference in influence explains environmental governance in the real world in a more comprehensive way. （3） After considering the regional and temporal heterogeneity, the research hypotheses are still robust. It is also found that compared with the haze environmental event in 2013, the economic event of the financial crisis in 2008 has a more obvious impact on the development strategy and environmental governance. （4） The mechanism test shows that the development strategy violating the comparative advantage makes enterprises lack viability, weakens environmental constraints, and leads to more serious fiscal deficit, thus reducing the level of environmental governance.

The policy enlightenment is that the optimal environmental governance is the endogenous result of the development strategy following the comparative advantage. The quality of environmental governance in a region does not depend on purely administrative and sporty environmental law enforcement, but on the viability of enterprises in its comparatively advantageous industries. Only when the company has viability, the government’s environmental governance policy can be effectively implemented and become a hard constraint. At the same time, when formulating fiscal policies and subsidy policies, the state needs to consider the externalities of environmental governance and the distortion of fiscal expenditures in environmental governance, and establish a regulatory mechanism to eliminate distortions.