AbstractThis study examines the impact of green bond issuance on companies' environmental social and governance (ESG) performances and greenwashing behavior of a sample of Chinese‐listed firms. We find that the issuance of green bonds significantly bolsters corporate ESG performance through the financing and signaling mechanisms. The moderating effect of policy uncertainty proves to have a mutually reinforcing effect on the impact of green bonds on ESG performance. By signaling the commitment to green and low‐carbon transformation, the issuance of green bonds offsets the negative effects of policy uncertainty on firm's ESG performance. Extended analysis on greenwashing discerns no notable differences among firms with different polluting conditions and politically connected levels. The issuance primarily improves environmental (E) and social (S) dimensions, with negligible influence on the governance (G) aspect of ESG. Our findings suggest that a potential propensity of greenwashing in China's green bond market.