 Carbon mitigation depends on both the force of government regulation and the autonomy of enterprises. Green fiscal policies can be used as a tool to encourage enterprises to reduce carbon emissions, but this effectiveness is limited without the presence of green investments. Therefore, it is important to understand how these two forces interact with each other in order to maximize the potential for carbon mitigation. This study examines the role of green fiscal policies and corporate green investment in promoting carbon mitigation. It finds that green fiscal policies can serve as a trigger for green investment, while green investment can act as a catalyst for green fiscal policies to achieve carbon mitigation. Additionally, the study shows that green fiscal policies can also be effective in reducing carbon emissions if they are combined with green investment. This article was authored by Youfeng Hu, Youqiang Ding, Zhen Liu, and others.