The containment leakage testing includes the Type A tests, Type B tests and Type C tests. Among them, Type A tests are tests intended to measure the primary reactor containment overall integrated leakage rate, and Type B tests and Type C tests are tests intended to measure the local leakage rate of containment such as penetrations and isolation valves. At present, the integrated leakage rate test (ILRT) interval of CPR1000 unit is 6 or 7 refueling cycles, and the duration of the test is about 85 h or more. The ILRT is a pressure test, which is destructive to the containment. Extending the ILRT interval can reduce the number of tests, which can improve the reliability of the containment, reduce the collective dose and shorten the outage time. In order to evaluate the feasibility of extending the ILRT interval, taking a CPR1000 nuclear power plant as an example, the risk of the test interval extension was analyzed and quantitatively calculated by using probabilistic safety assessment method. The results show that the risk of the ILRT interval extension of CPR1000 unit is acceptable, and it is feasible to extend the interval from the perspective of risk. The study in this paper can provide a basis from the perspective of quantitative risk and can be used to support the risk-informed integrated decision making for the ILRT interval extension of CPR1000 unit.