A start-up time of a production facility is shortened while generation of a muting error is suppressed, whereby productivity is improved. A multiple-optical-axis photoelectric sensor system (100) includes a projector (1), an optical receiver (2), a light blocking determination unit configured to make a light blocking determination whether each of optical axes formed between the projector (1) and the optical receiver (2) is in a light blocking state, and a muting processor configured to temporarily disable the light blocking determination on condition that a detection signal input from an external muting instrument changes according to a predetermined sequence. The muting processor determines the sequence of the detection signal from the muting instrument during the muting by dividing the sequence into a plurality stages. The muting processor accumulates and analyzes measurement information acquired in each stage, and decides an optimum setting value for a muting operation condition based on an analysis result.