Aiming at the problem that learning interests and motivation of some university students are not strong enough, the influence factors of learning interests were analyzed from the aspects of society, family, teacher and so forth. The subtle-type and direct action-type influence factors were proposed. On this basis, the principle of improving the learning interest was given, the stimulation method of learning interest for classroom teaching was discussed. Finally, the calculation of normal section flexural capacity of bending member in the course “Basic theory of reinforced concrete structure” was taken as an example to introduce the sorting logic of knowledge and to discuss the innovation of teaching mode and the application of new technique in the classroom teaching.