There are provided a photoelectric sensor and a photoelectric sensor system in which received light quantities of a plurality of photoelectric sensors are displayed in an integrated manner, and slight variation in the received light quantity that has nothing to do with a detected condition of a workpiece is ignored and a photoelectric sensor with abnormity is easily found out. Upon acceptance of an instruction to execute scaled display by a control unit of a photoelectric sensor, a scaling adjustment ratio is calculated by assigning the received light quantity to a target value set to be greater than a display upper limit while executing the scaled display. A received light quantity that is subsequently obtained is scaled based on the calculated scaling adjustment ratio to obtain a received light quantity after the scaling.