Abstract: A new method for the detection of the bystander effects of heavy ion radiation on tumor cells was proposed.A model was established mainly based on the signal factors that were secreted by cells after radiation to influence cells without radiation by means of the culture medium transfer experiment.This model was in accordance with actual measurements and convenient for computation.This method was used to simulate neural tumor cells affected by heavy-ion radiation in vivo and investigate the changes in the proliferation and apoptosis of cells not irradiated but cultured in the media harvested form the irradiated cells.Simulation results indicated that neural tumor cells will release special signal molecules after radiation,and these molecules can inhibit the proliferation of normal cells.Moreover,the inhibition effect was proportional to the time and dosage of heavy ion irradiation.