To provide a photosensitive material detector capable of preventing the occurrence of sensor fogging of the photosensitive material even in the case of an infrared film and effective for the actual carrying section of the photosensitive material.

This detector for the photosensitive material 2 is constituted so that photoelectric sensors 101, 102, 103 and 104 adopting a light emitting diode(LED) whose wavelength is within the range of 1050 nm-1550 nm and has a peak between ≥1200 nm and ≤1400 nm as a light source are arranged in a dark room 1. Then, the plural photoelectric sensors are arranged in the dark room 1 and divided into plural blocks A and B. Besides, a control means for independently controlling the power sources 3 and 4 of the sensors belonging to the respective blocks is provided. One block is constituted of a sensor group for directly irradiating the photosensitive material with the light of the sensors. It is preferable that the photoelectric sensors are arranged at the block constituted of the sensor group for directly irradiating the photosensitive material with the light of the sensors out of the plural blocks.