A photoelectric sensor includes a connecting section for light projection to which a light propagation member for light projection optically coupled to a light emitting element is connected, a connecting section for light reception to which a light propagation member for light reception optically coupled to a light receiving element is connected, a signal generating unit configured to compare a light reception signal generated by the light receiving element and a threshold and generate a detection signal indicating a result of the comparison, an light emitting element for indication optically coupled to at least one of the connecting section for light reception and the connecting section for light projection and configured to emit visible light, and a control unit configured to light the light emitting element for indication on the basis of an instruction from an outside.