Based on the 2016-2021 Chinese A-share listing data, this paper empirically explores the impact of corporate excess goodwill on the level of green innovation and its mechanism of action, taking into account the life cycle status of enterprises. It is found that excess goodwill has a significant negative impact on the level of corporate green innovation, and this conclusion still holds after the robustness test using multiple methods. The adjustment analysis shows that the enterprise life cycle delay weakens excess goodwill's inhibitory effect on green innovation. Heterogeneity analysis shows a more significant negative effect of excess goodwill on corporate green innovation among companies that are not heavy polluters, in the eastern region, and with high technology. The research in this paper is instructive for promoting corporate reform and governance to achieve peak carbon attainment and carbon neutrality.