High temperature magnetic properties of the SmCo7 films deposited on Si(100) substrate with Mo underlayer were investigated. The results show that the effects of high temperature aging treatment on the crystal structure and the magnetic properties of the films are not obvious. According to the law of approach to the saturation and high temperature magnetization curves of the films, the temperature dependence of magnetic anisotropy constant K1 can be obtained, which clearly suggests that the preferred orientation of SmCo crystalline will be destroyed at a certain extent by elevated temperatures. Moreover, the proper temperature dependence of magnetic properties for the films, is suitable for applications in microelectromechanical system (MEMS).