Since the reform and opening up, the rough-and-ready development model has brought about economic take-off, but it has also paid a huge price in terms of resources and environment. Under the double pressure of slowing economic growth and serious damage to the ecological environment, the intensity of China’s environmental regulations has been increasing, and in 2013, eight provinces and municipalities began to implement a pilot policy of carbon emissions trading. At the same time, the scale of China’s Outward Foreign Direct Investment (OFDI) has been increasing. Regarding the relationship between environmental regulation and OFDI, most scholars currently study it from the perspective of host-country environmental regulation, and fewer study home-country environmental regulation. Using provincial panel data for a total of 11 years from 2009 to 2019, this paper constructs a double-difference model based on the carbon emissions trading pilot policy in eight provinces and cities in China as a quasi-natural experiment and explores the relationship of home-country environmental regulation on China’s OFDI.