In recent years, fintech has rapidly developed on a global scale, bringing about significant transformations across various industries. Particularly in the energy sector, the potential of fintech to promote corporate green investment has increasingly become a focus. As the energy industry accounts for a significant proportion of global greenhouse gas emissions, guiding companies in implementing green investment has become an important issue for environmental protection and sustainable development. However, previous studies have rarely systematically investigated the influence of fintech on corporate green investment in the energy industry and the mechanisms involved. Hence, this study aims to bridge this research gap within the context of China. By utilizing valid survey data from 466 corporations in the Chinese energy industry and the method of structural equation modeling, the results indicate that: (1) Fintech can promote corporate green investment in the energy industry. (2) Fintech can promote corporate data-driven decision-making capability, information transparency, and sustainable development strategy. (3) Data-driven decision-making capability, information transparency, and sustainable development strategy can also promote corporate green investment in the energy industry. (4) Mediation analysis reveals that data-driven decision-making capability, information transparency, and sustainable development strategy each play a mediating role in the impact of fintech on corporate green investment. (5) Comparative analysis of the mediation effects indicates that there is a certain degree of difference among these three variables’ mediating effects, but it did not reach a statistically significant level. This study provides rich insights for business practices, encouraging companies to strengthen their focus on green investment in the fintech era and offer guidance and recommendations to relevant stakeholders, thereby providing practical guidance for corporate green transformation and sustainable development. Finally, this research also contributes to policy development and optimization.