Green finance is increasingly becoming a new trend in global capital markets. To better integrate new development concepts and strengthen financial support for the real economy, continuous improvement of the capital market information environment and higher standards for green practices are required. ESG ratings, by integrating non-financial information, serve as a crucial tool in improving the overall information landscape. This research investigates how corporate ESG performance affects stock price synchronicity, employing a dataset of non-financial A-share firms listed in China over the period from 2009 to 2023. The findings reveal a notable positive relationship between corporate ESG performance and the degree of stock price co-movement, which aligns with the noise trader hypothesis. Even after robustness tests, the main findings still hold true. Furthermore, the heterogeneity analysis indicates that the positive relationship is more evident among firms that receive greater media coverage, face fewer financing constraints, and operate in less competitive industries. The findings contribute to the body of literature on the economic implications of corporate ESG performance and enhance the understanding of the factors influencing stock price co-movement, providing practical insights for improving ESG systems, emphasizing corporate sustainable development, and guiding medias and investors attention to non-financial information.