Under the constraint of the “double carbon” goal, enhancing access to green finance, reducing financing challenges, and tackling insufficient investment in renewable energy enterprises are of great value for the green economy. Based on the panel data of Chinese A-share listed enterprises from 2010-2020, this paper uses the Difference-in-Difference method to study the impact of green credit policy on the investment and financing behavior of renewable energy enterprises, leveraging a policy experiment in China, called “Guidance on Building a Green Financial System” issued in 2016. The results show that the financing cost of renewable energy enterprises has significantly decreased, and the financing cost of small, non-state-owned enterprises has decreased more obviously. The investment scale of renewable energy enterprises has significantly increased, and the investment scale of small renewable energy enterprises has increased more obviously, indicating that green credit has a significant financing promotion effect and investment incentive effect on renewable energy enterprises.