Capsule endoscope, widely used in the observation of the internal space of the human body, has the advantages of small volume, long battery life, no pain and so on. However, the traditional capsule endoscope has the disadvantages of small observation range, low relative illumination and low image quality. The capsule endoscope lens with large imaging range, high relative illumination and high resolution is designed in this paper. The design result of the lens show that the FOV is 150°, the F number is 2.8, the total length is less than 6 mm and the average relative brightness in the field of view is over 90%. In order to achieve the high image quality of the lens, the modulation transfer function (MTF) exceeds 30% at 200 lp/mm. The capsule endoscope, which has a compact structure, uses only five spherical lens and and is helpful for medical staff to accurately judge the condition.