An optical element includes a light receiving surface 101 covering a light source on a plane and an exit surface 103. When the central axis is AX, the intersection of AX with the plane is P0, and in a cross section containing AX, an angle between a line connecting P0 and P on 101 and AX is θr, an angle between a normal to 103 at Q and AX is ϕ, a distance from AX to Q is r, the maximum value of r on 103 is rmax, and θr and ϕ are positive when measured clockwise with respect to AX, ϕ has plural positive local maximum and minimum values as a function of r in 0.5rmax≤r, in an area of 103 through which a ray travelling from P0 at a positive angle θr passes, and the shape of 103 is symmetric with respect to AX.