An iris recognition lens composed of three plastic aspheric lens for mobile phone application is designed. The pixel size of focal-plan array detector complementary metal oxide semiconductor (CMOS) chip is 1.12 μm. The F number of the designed lens is 2.0, the field of view is 32.6°, and the total length is 4.0 mm. At the optimal work distance of 320 mm, the modulation transfer functions (MTF) of all fields at 1/2 Nyquist frequency are larger than 0.45, the optical distortion is less than 1.2%, and the relative illumination is higher than 87%. The optical system has the advantages of simple structure, small volume and excellent image quality.