Objective To investigate the effects of insole parameter changes on biomechanical mechanism of heel pain by finite element methods. Methods The 3D finite element model of foot, crus bones, gastrocnemius muscle and knee joint was reconstructed based on CT images. The plantar pressure distribution and peak pressure were calculated by changing the shape, thickness and hardness of the insole. Results The distribution of plantar pressure calculated by the finite element model was generally consistent with that measured by the pressure plate, and the values were very close. Compared with the barefoot standing, the peak pressure of the heel was decreased by 20.5%, 59.2% and 38.4%, and that of the metatarsal head was decreased by 9.9%, 18.1% and 46.7%, with flat insole, half-contact insole and full-contact insole, respectively. For patients with heel pain, the pressure peak of the heel and the metatarsal head at plantar surface decreased with the conventional thickness of insole increasing and the hardness of insole decreasing. Conclusions The changes in insole parameters have a significant influence on the plantar pressure distribution. Finite element analysis can contribute to discovering the etiology and pathology of heel pain, so as to provide the theoretical basis for clinical treatment.