Existing studies have shown that environmental tax reform (ETR) in China has a significant effect on green innovation (GI), but there is no in-depth study on the heterogeneous effects of different types of green innovation. Using the data of listed companies in China’s high-pollution manufacturing industry from 2012 to 2020, this paper adopts the difference in differences (DID) method to study the differentiation effect of ETR’s signal effect and resource crowding-out effect on different green innovation. The empirical results indicate that ETR may significantly improve green product innovation through signaling effect, while reducing green process innovation through resource crowding-out effect. Further moderating effect studies show that enterprises with high institutional corporation social responsibility (ICSR) strengthens the positive effect of ETR on green product innovation. However, enterprises with high technical corporation social responsibility (TCSR) enhances the negative impact of ETR on green process innovation. This paper offers valuable implications for government green governance and enterprises' green transformation.