Abstract: Based on the life cycle assessment method, inventory data of hardwood used in direct combustion power generation was established. The ILCD Midpoint+ method was used to evaluate six environmental impact types, and the main pollutants causing various environmental impacts were analyzed. At the same time, multiple power generation methods were compared in terms of six environmental impact types. Results show that the environmental impact of the direct combustion of hardwood for power generation mainly comes from the planting process and power generation process, with global warming mainly coming from the power generation process, and the other five types of environmental impact mainly coming from the planting process. Nitrogen oxide, sulfur oxide, ammonia and greenhouse gas are the main factors causing environmental impact of each unit process. In terms of environmental impact, compared with hydropower, wind power, and photovoltaic power generation methods, hardwood direct combustion power generation has certain disadvantages, but its environmental impact is much lower than traditional fossil energy power generation methods.