In this paper, a design method of the golden spiral tooth profile of short flexspline harmonic drive is presented to further improve the meshing performance of the short flexspline harmonic reducer. The expression of the pressure angle on the reference circle of the golden spiral gear is established, and the parametric equation of the tooth profile of the flexspline is obtained. Based on the theory of harmonic drive meshing and tooth envelope, the conjugate circular spline tooth profile is obtained. The meshing state diagram of the flexspline and the circular spline is drawn, which proves that the flexible circular spline does not interfere. The meshing performance is studied, transmission backlash and envelope interval are calculated. By comparing with involute tooth profile, it is found that golden spiral harmonic tooth profile drive has smaller backlash and larger envelope interval. After that, the spatial tooth profile of the FS is modified by adjusting the thickness of the flexspline. On this basis, the finite element model of short flexspline harmonic golden spiral reducer with complete bearing is established by Abaqus and the finite element simulation experiment is carried out. The results show that the short flexspline harmonic golden spiral reducer has many meshing teeth, high transmission accuracy and small return difference. The transmission performance and the meshing performance are good, can achieve high precision transmission. It provides a theoretical basis for the development of the short flexspline harmonic gold spiral drive technology.