With the increasing awareness of sustainable development, ESG performance has gradually become the focus of attention for enterprises and their stakeholders. Driven by the goal of becoming a financial power and artificial intelligence technology, digital finance platforms have rapidly emerged and deeply applied algorithmic technology to the traditional financial industry, bringing opportunities for the sustainable development of enterprises. In the existing literature studying the relationship between digital finance and corporate ESG performance, the impact mechanisms mainly focus on the financial and technological support brought by digital finance, while there is still a lack of research perspectives on the impact on the dimensions of ESG. This paper employs the digital finance index from the Peking University Digital Inclusive Finance Index and the Huazheng ESG Rating Index to investigate how digital finance affects corporate ESG performance. The findings are as follows. Firstly, digital finance can enhance corporate ESG performance. Secondly, from the perspective of ESG dimensions, digital finance primarily enhances corporate environmental performance by promoting the increase of green investment and the strengthening of environmental management. It also boosts corporate social performance by narrowing internal pay gaps and improving product quality. Furthermore, digital finance elevates corporate governance performance by increasing analysts’ attention and strengthening internal controls. Thirdly, digital finance can significantly enhance the ESG performance of enterprises with high green total factor productivity, high product market competitiveness, and a high level of Confucian culture. Fourthly, from the perspective of the dimension of digital finance, digital finance primarily promotes corporate ESG performance through the breadth of coverage and the use of depth dimensions. Compared with previous literature, the marginal contributions of this paper may lie in the following two aspects. Firstly, in terms of research methodology, this paper delves into the impact of digital finance on corporate ESG performance, utilizing the Bartik instrumental variable to effectively mitigate the issue of reverse causality between the two. This not only identifies the causal relationship between them more accurately, but also contributes to enriching academic research on the drivers of ESG performance. Secondly, in terms of research perspective, this paper analyzes the influence mechanisms and heterogeneities from the three subdivisions of ESG performance, enriching the understanding of the impact mechanisms of digital finance on corporate ESG performance and the research on the three subdivisions of ESG. This can provide thoughts and references for future related studies. To a certain extent, this study enriches the understanding of the mechanisms underlying the impact of digital finance on corporate ESG performance, which can assist enterprises in better implementing sustainable development strategies. It holds significant practical value in promoting Chinese enterprises to fulfill their “dual carbon” responsibilities and practice green development.