To perform quasi-experimental designs based on China’s policies of green finance reform and innovation pilot zones constructed in 2017, heavy-polluting enterprises listed as A-shares on the Shanghai and Shenzhen Stock Exchanges from 2010 to 2019 were selected as study samples to explore the influence of green finance on environmental violations of such enterprises by means of a double difference model. The results showed that green finance significantly suppresses environmental violations in heavy-polluting enterprises. Through mechanism analyses, it is demonstrated that such a suppression effect of green finance is generated primarily by improving environmental protection management systems in these enterprises and raising their environmental protection expenditures. During heterogeneity tests, green finance is found to exert a more significant inhibitory effect on environmental violations in large-sized enterprises, enterprises in Eastern China, and enterprises with a high management shareholding ratio.