According to the needs of rehabilitation training for stroke patients after operation, a mechanical device of lower limb stretching device was developed and designed based on ergonomics and rehabilitation medicine, and according to sequence training method. The selection of design parameters and the overall design idea of the rehabilitation equipment are introduced. The training units are designed according to the requirements of the sequential training method. Three-dimensional simulation and kinematics analysis of the whole lower limb stretching device and rehabilitation units were carried out, and kinematics simulation was carried out with software ADAMS. The engineering prototype was tested in clinic.