An optical element having an optical surface and at least three convex portions on a surface different from the optical surface, wherein, among the at least three convex portions, two convex portions a space between whose centers is a maximum and one convex portion a length of a perpendicular from whose center to a straight line connecting centers of the two convex portions is a maximum satisfy a relationship of tan−1 (h/p)≦a first specification value, wherein h is a greater one of heights of the optical element at centers of the two convex portions with reference to a tangential plane of the optical element at a position of a foot of the perpendicular, and p is a length of the perpendicular.