This paper explores the effects of innovation input, human resource management and government support on innovation performance of enterprises. An empirical model is built based on military enterprises, collect data of 20 military enterprises from 2007 to 2015 and a regression model is built to test our hypotheses. Research results show that innovation input, employee welfare, policy environment and government subsidy positively affect innovation performance of military enterprises. The complementary effect of innovation input and employee welfare is also found. In addition, this paper finds that policy environment negatively moderates the relationship between human resource management and innovation performance of military enterprises. Research results of this paper serve as an effort to elicit more research on innovation machanism of military enterprises and provide military enterprises with important suggestions and practical implication.