To provide a photoelectric sensor which achieves increased improvement in performance by making the amount of light from a light projection element increase and preventing the size of a light receiving spot in a light receiving element from increasing. A photoelectric sensor includes a lens which is installed on a light projection element (11) and at a position facing a light projection lens (12), and in which a curvature in a direction orthogonal to a straight line passing through the center of the light projection lens (12) and the center of a light receiving lens (13) is larger than a curvature in a direction parallel to the straight line passing through the center of the light projection lens (12) and the center of the light receiving lens (13).