Abstract: The case library construction of materials mechanics involves the knowledge points, the related situations and the problems as three elements of a case, and integrates various case resources, such as teacher's notes, the graduate recommendations and the selected student notes. The teaching design based on the case library aims to cultivate students' ability to find, analyze and solve problems, and to strengthen their practical awareness and safety awareness. With various professional backgrounds and disciplines, the Internet-based teaching, the "mechanics on the fingertips", is effectively put into practice through meticulously selected cases and interactive discussions in class and after class, to promote the sharing of online and offline resources, the interactions between teachers and students in and out of class, and the in-depth integration of problem analysis and problem solving.