Abstract: In order to improve the comprehensive utilization efficiency of coal slime, the coal slime drying technology was coupled with the coal slime mixed combustion power system. Coal slime mixed combustion power systems integrating with steam/air drying were constructed. Based on the basic law of thermodynamics and the theory of technical economy, analysis models of thermo-economic and techno-economic for the system were established, respectively. Energy, exergy and economic analyses on the system of a 660 MW coal-fired unit were carried out. Results show that the coal saving capacity of the coal slime mixed combustion power systems integrating with steam/air drying is 2.07-9.44 g/（kW·h） and 1.19-5.43 g/（kW·h）, respectively, when the coal slime ratio is 25%-90%. The energy saving essence of the system is that heat source in the drying process before coal slime furnace is low-grade energy rather than the high-grade energy, which reduces irreversible loss in combustion process and exergy loss in flue gas emissions. Payback periods of the coal slime mixed combustion power systems integrating with steam/air drying are 5.0 years and 3.1 years, and the maximum net present values in 20 years are 6.941 million yuan and 5.405 million yuan, respectively. From the perspective of thermodynamics/technology and economy, the performance of the coal slime mixed combustion power systems integrating with steam/air drying is better when the power plant remaining life is less than 8.9 years.