With the rapid development of artificial intelligence (AI) technology, manufacturing enterprises are gradually entering the wave of digital and intelligent transformation. However, whether AI technology can empower corporate green innovation and the underlying mechanisms of their interaction remain unclear. Based on panel data of listed manufacturing companies in Shanghai and Shenzhen A-shares from 2010 to 2023, this paper employs a double fixed-effects model to explore how AI influences corporate green innovation and analyze the mediating mechanisms of AI's empowerment of green innovation. The findings reveal a nonlinear "U-shaped" relationship between AI and corporate green innovation, where AI first inhibits and then promotes green innovation. Absorptive capacity and human capital play "U-shaped" mediating roles in the relationship between AI and green innovation. The "U-shaped" effect of AI on green innovation is significant in small-scale enterprises, non-state-owned enterprises, enterprises with low competition intensity, and high-tech enterprises. Media attention positively moderates the "U-shaped" relationship between AI and corporate green innovation. These conclusions enrich the research on the nonlinear relationship between AI and green innovation and contribute to revealing how AI can empower corporate green innovation.