An image pickup lens assembly comprises three lens groups, from the object side to the image side: a first lens group, a second lens group, and a third lens group. The first lens group includes two lenses with refractive power, namely, a first lens with positive refractive power, and a second lens with negative refractive power. The front surface of the first lens is convex, and the rear surface of the second lens is concave. The second lens group includes a meniscus third lens with positive refractive power, the rear surface of the third lens is convex. The third lens group includes a fourth lens with negative refractive power, the front surface of the fourth lens is convex, and the rear surface of the fourth lens is aspheric. An aperture stop is located between the first lens and the second lens of the first lens group for controlling the brightness of the optical system.