In view of the lack of systematic organization and planning in the process of practical innovation training in our university, which leads to poor implementation effect and other problems, this paper puts forward the construction of "four levels of progressive diversification" and "four in one" extracurricular scientific and technological practice system. It designs the process of guidance and inspiration from the simple to the deep, and pays attention to the cultivation of students' interest in learning and their desire for professional knowledge. The progressive extracurricular scientific and technological practice system complements and extends the "three three types" applied talents training system of "theory combined with practice, teaching combined with scientific research, popularization combined with improvement", which is helpful to the realization of the training objectives of applied talents.