To provide an image pickup lens capable of sufficiently suppressing flare caused by unnecessary diffraction order light.

The image pickup lens 7 comprises, in order from the object side to the image surface side, an aperture stop 5, a first lens 1 having positive power, a second lens 2 having negative power and configured from a meniscus lens having a concave lens surface on the image surface side, a third lens 3 having positive power and configured from a meniscus lens having a convex lens surface on the image surface side, and a fourth lens 4 having negative power and having aspherical lens surfaces on both sides, the lens surface on the image surface side being a concave surface in proximity to the optical axis. A diffraction optical element is formed on the lens surface on the image surface side of the first lens 1. When the number of diffraction ring zones in the effective diameter of the lens surface on which the diffraction optical element is formed is three or less, the focal length of the entire optical system is taken as f, and the focal length of only the diffraction optical element is taken as fDOE, the following conditional expression (1), that is, fDOE/f>30 is satisfied.