With the continuous expansion of radiological diagnostic equipment in Chinese general hospitals, the design quality of radiation protection engineering directly affects the radiation safety of medical staff, patients and the surrounding public. This study introduces the concept of the entire life cycle into the field of assessment of the design quality of radiation protection engineering. By identifying the quality influencing factors in each stage including planning and design, construction implementation, operation and maintenance iteration, as well as decommissioning disposal, an assessment index system was constructed, the model application scenarios in different stages were clarified, and a guarantee mechanism was proposed from three dimensions: organizational system, technical data, and personnel capability. The research results can provide some reference for the whole life cycle management of the design quality of radiation protection engineering in general hospitals, so as to reduce the radiation safety risk and improve the long-term effectiveness of radiation protection engineering.