The invention provides a transmission type photoelectric liquid level meter. The liquid level meter comprises light generating devices, light receiving devices, a photoelectric sensor signal processing circuit, a mounting flange, first compression nuts, second compression nuts, a first transparent tube, a second transparent tube, a first locating rod and a second locating rod, wherein the light generating devices are fixedly connected with the first locating rod; the light receiving devices are fixedly connected with the second locating rod; the photoelectric sensor signal processing circuit comprises a light signal processing circuit, a temperature sensor circuit, a pressure sensor, a singlechip circuit, a power circuit and a display circuit; the light receiving devices receive the lightsignals sent by the light generating devices; the light receiving devices are electrically connected with the light signal processing circuit; and the light signal processing circuit is used for processing the light signals received by the light receiving devices. The liquid level meter has simple structure, is convenient to use and can correct the effects of sensor property variation, measured medium optical characteristic variation and measured medium temperature and pressure variation on the measured value of the liquid level.