It is of great significance to study the impact and mechanism of political turnover on enterprise environmental protection investment (EEPI) under the government environmental performance appraisal system. In this paper, we investigate how political turnover affects enterprise environmental protection investment based on the data of Chinese share listed companies from 2009 to 2018. The results show that political turnover has a significantly positive effect on EEPI. Moreover, we provide evidence that collusion deterrence and official promotion incentive are the mechanisms through which turnover of local officials promotes enterprises to increase investment in environmental protection. Additional moderating tests show that the degree of market competition strengthens the positive impact of political turnover on EEPI, while provincial environmental competitiveness inhibits this relationship. This paper analyzes the enterprise environmental governance mechanism from the perspective of political economy, which has enlightenment significance for the improvement of the Chinese government’s environmental supervision system and the construction of ecological civilization.