Abstract: In order to establish a simple and feasible method of environmental risk assessment and classification of radioactive source repositories, the dangerous index of radioactive source storage was determined as the environmental risk classification index based on the influence analysis of the key risk factors of radioactive source repositories. Based on the characteristics of the continuity of the risk index and level range for radioactive source storage, a quantitative characterization model for the environmental risk classification indicators of radioactive source repositories was constructed. Relevant correction coefficients were introduced to establish a method for calculating the environmental risk index and classifying the environmental risk level of radioactive source repositories. Case application results show that the environmental risk assessment and classification method established in this study has strong applicability and good operability and can effectively support the environmental risk prevention and management of radioactive source repositories.