Abstract: Aiming at the inconsistency in forward and reverse transmission performance caused by asymmetric tooth profiles in the swing roller movable teeth transmission, a symmetric tooth profile design method for the swing roller movable tooth transmission and its parameter selection strategy is proposed. Firstly, by establishing an equivalent mechanism model with replacing high pairs with low pairs, the tooth profile equations of the wave generator and the ring gear were derived. Secondly, through the mechanism conversion method, the radial angle of the ring gear tooth profile corresponding to the motion path of the movable tooth in the push and return section is deduced. Finally, taking tooth profile symmetry as a constraint, the selection strategy of swing center distribution circle radius of movable teeth and swing coefficient parameters is formulated. The results indicate that, compared with asymmetric tooth profiles. The results show that the mean value of the positive and negative meshing force of the symmetrical gear reducer is 6.67 N and 3.14 N lower than that of the asymmetric gear reducer, and the variance is 31.32 and 6.10 lower, which verifies the feasibility and effectiveness of the method. The research findings can provide theoretical guidance for the design and parameter selection of symmetrical tooth profiles for the swing roller movable teeth transmission.