Abstract: As an important parameter for the calculation of the radioactive source term released to the environment, the value of containment bypass leakage of nuclear power plant shall directly affect the result of accident consequence assessment. The reasonableness of the bypass value is related to the rationality of the division for the exclusion area, the low population zone and the emergency planning zone. Therefore, it is focused in the review of the safety analysis and environmental impact assessment. For enhancing the nuclear safety and radiation protection design of HPR1000, the value of 10% of the primary containment bypass was discussed from two aspects. One of them is an analogy with related M310+ experiment data. The other is the influence analysis of different bypass values on the accident source term and consequences. The results proved that the influence of containment bypass on the accident source term cannot be ignored, but its impact on the off-site dose consequences is not obvious. The value of 10% of the primary containment bypass for HPR1000 is able to envelope the experiment data and effectively reflect the contribution of bypass leakage to the off-site dose consequence. It is considered reasonable in the engineering application of HPR1000.