The heat generation during metal cutting processes affects accuracy of the machined surface and strongly influences cutting forces and tool wear. Material property of coated tools is one of the most important factors effecting heat conduction and temperature on the rake face of coated tools. To find the action of thermal properties of coated cutting tools on cutting temperature, the temperature distributions were obtained with temperature-dependent properties and temperature-independent properties of coated tools using numerical method. The results indicated that temperature-dependent properties should be considered when calculating cutting temperature. To simplify calculation, selecting the thermal conductivities at average temperature to substitute for temperature-dependent properties can reduce calculating error. The conclusion provides a methodology for analysis of cutting temperature of coated tools, design of cutting tools and analysis of thermal stress within coated tools in manufacturing industries.