Based on the comprehensive design experiment course "comprehensive heat treatment of composition, process, structure and performance of structural steel", the virtual experiment of composition, process, structure and performance of structural steel is designed and built. The design and implementation of comprehensive and design virtual experiment of heat treatment are introduced. Virtual experiment is not limited by experimental time, space and hardware resources, and has many advantages that real experiment does not have. Compared with the experimental teaching effect, the application of virtual experiment in auxiliary experimental teaching can make up for the deficiency of real experimental teaching and improve the quality of experimental teaching obviously.