The invention relates to an optical sensor reliability testing system and testing method. The optical sensor reliability testing system is characterized by comprising an environmental test chamber used for containing an optical sensor sample to be detected and adjusting the test environment in dependence on the reliability test type; an optical signal emission and detection unit used for emitting a detection optical signal to the optical sensor sample to be detected, receiving a feedback optical signal of the optical sensor sample to be detected, and converting the detection optical signal and the feedback optical signal into corresponding digital quantity signals; a merging unit used for merging the corresponding digital quantity signals of the detection optical signal and the feedback optical signal, and obtaining the light intensity data of the optical sensor sample to be detected; and a monitoring device used for assessing the reliability of the optical sensor sample in dependence on the light intensity data. The optical sensor reliability testing system and testing method can be widely applied to reliability tests of optical sensors.