Abstract: To study the mechanism of grinding force and improve the machining quality, a theoretical model is established based on grinding force analysis after discussing the surface temperature of workpiece. The grinding force is divided into two parts, namely cutting force and friction force to study their relationship with processing parameters. The calculated tangential forces, combined with their relations with heat source intensity, are used to establish the theoretical model of highest temperature on ground surface. The constants are confirmed by grinding tests on 45 steel and thus confirming the model. Results show that the surface temperature increases with the increase of cutting depth, infeed speed and wheel speed, and that the maximum relative error between the surface temperatures of model and experiment is 5.04%, while average relative error is 2.47%. In conclusion, theoretical model based on grinding force could be used to analyze the temperature filed on ground surface and improve the surface quality.