Courses related to SCM are necessary for students major in electronics and electromechanics in secondary vocational schools. In teaching practice SCM is often thought too difficult and the result is not so ideal. A trinitarian teaching method of project case, software simulation and CDIO is pointed out in this research, which is effective in stimulating learning interest, improving creativity and performance. Meanwhile this method focus on teaching characteristics of secondary vocational schools, and better teaching result is obtained.