Abstract: In China, ESG funds are still in the early stage of development, and how to improve their performance level has become an urgent problem. Based on 26 ESG funds in 2018–2021, we use the DEA-Malmquist productivity index method to evaluate the performance of ESG funds at two levels, static and dynamic, and apply the fsQCA approach to explore the performance improvement path of ESG funds. Overall, ESG funds perform well, but there are significant differences among them. The total factor productivity of ESG funds shows a decreasing trend during the study period. There are three paths to improve the performance of ESG funds. The 1st path is to maintain a low concentration of holdings and reduce the frequency of fund position adjustments based on increasing fund size. The 2nd path is to diversify into stocks with high ESG scores based on increasing fund size. The 3rd path is to hold stocks with high ESG scores for a long time based on increasing fund size. Concerning the results of the empirical analysis, it proposes to improve the ESG rating system, broaden the market scale of ESG funds at a steady gait, and gradually optimize fund managers’ investment strategies.