Abstract: The three-stage DEA model is used for the empirical analysis of the safety input-output efficiency of 17 listed coal companies in China. The results show that three environmental variables, including enterprise size, employees’ labor productivity and education level, positively affect safety efficiency. After eliminating the influence of environmental variables and random errors, the average value of the technical efficiency and pure technical efficiency increases, while the average value of the scale efficiency decreases, and the overall safety input-output efficiency of coal mine enterprises is higher; low scale efficiency is the main reason for restricting the output efficiency of safety investment. Coal mining enterprises should improve their scale allocation capacity, optimize their investment structure of safety funds, and improve their technical efficiency and management level.