Abstract: Maritime fishing is a major component of the agricultural industry of Zhejiang Province. It faces substantial risk; especially that natural disaster will incur great loss on fishing industry and cause severe safety problems. Government fiscal support is essential to the development of maritime fishing insurance. This article adopts the externality theory of wealth economics to articulate the reason for the essentiality of fiscal support for maritime fishing insurance. Based on the theory, empirical study is conducted through DEA model to investigate the efficiency of fiscal support. The sample data is collected from Zhejiang maritime fishing mutual insurance association, across a period of 2005 to 2014. Results show that the efficiency of local fiscal support for maritime fishing insurance in Zhejiang province is high; diminishing returns to scale has appeared in some of the areas, which means that the scale of fiscal support is saturated under current approach, it is necessary to achieve innovation on management and business strategy.