To improve the convenience and effect of fitting process, an online fitting system of user-personalized body type based on the virtual technology is put forward. Firstly, develop the fitting system with Java as the development language, and construct the human model, spinning motion model and virtual clothing model; then, divid the relevant model creation based on the body, generate the personalized body type, and design the slab model, represented by triangular patch, while all points in same one gender model keep the spatial position relation with each other to simplify the interpolation process; finally, verify the efficiency of developed system through the factor analysis and cluster fitting design.