Reinforcement corrosion is the main cause of the concrete structure failures. The service life prediction of the corroded reinforced concrete structures is of great significance to the reduction of economic loss of the project and safe operation of the structure. Aiming at the problem of service life prediction under different life assessment criteria, the time varying reliability index of the structure is obtained through the statistical characteristics of resistance and load effect using probability analysis reliability method, based on the test results of structural durability status. According to the index, the crack width life and bearing capacity life of the structure can be analyzed and predicted. The case study of an arch dam orifice and the crane girder of a hydropower house was carried out for the analysis. The results show that the dynamic reliability index of the structure decreases with the increase of service time, and the life prediction result of probability analysis method is within a reasonable prediction range. The study can provide decision making support for the maintenance and reinforcement of reinforced concrete structures in practical projects.