The work aims to research the design and cushioning performance of triangular corrugated cushioning insert aiming at the problem that the design of corrugated cushioning structure fails to form a complete system. First, through an analysis on the cushioning mechanism and theory of triangular corrugated structural members, the cushioning and critical load characteristics of triangular corrugated cushioning insert were obtained. Then, on the basis of triangular support structure, the overall plan of triangular corrugated cushioning insert was established according to the cushioning and critical load characteristics of triangular corrugated structure. Finally, the structural design method and procedure of triangular corrugated cushioning insert were applied to the actual design case of corrugated cushioning structure, and the cushioning performance of triangular corrugated cushioning insert was verified through the static compression test. The design example of triangular corrugated cushioning insert showed that the design scheme of triangular corrugated cushioning insert could be used in the actual design and development of corrugated cushioning structure, providing a basis for the calculation of corrugated cushioning structural members. The stress-strain curve and the design method of triangular corrugated insert thickness and bearing area obtained herein can guide the cushioning design of triangular corrugated insert structure in practical application and improve the design efficiency of cushioning structure.