The invention provides a method and system for evaluating the reliability of a low-voltage circuit breaker contact system, and the method comprises the following steps: S1, carrying out the simulationanalysis of the temperature rise of a wiring terminal of the contact system in a plurality of contact states, and obtaining a plurality of first temperature rise results; S2, actually measuring the temperature rise of the terminal in the working state to obtain a second temperature rise result; and S3, comparing the second temperature rise result with the plurality of first temperature rise results, and judging the reliability of the low-voltage circuit breaker according to a comparison result. According to the method for evaluating the reliability of the low-voltage circuit breaker contact system provided by the invention, the temperature rise of the wiring terminal of the contact system in various contact states is obtained through analog simulation, and then the actually measured temperature rise is compared with a simulation result to judge the contact state of the contact system, so that online evaluation is realized, and meanwhile, the evaluation method is high in accuracy.