A multi-element lens for controlling defocus and eye diopter for prevention and treatment of myopia and hyperopia. The multi-element lens includes one large unit convex lens for generating large defocus. One small unit concave lens for generating small defocus or focus through combination is combined on the lens of the large unit convex lens, or one small single lens is separately provided on the large unit convex lens. When an eye watches different distances through the lens, the central view region is in a small nearsightedness defocus or focus state, or a small farsightedness defocus or focus state, whereas the equatorial view region is always in a nearsightedness or farsightedness defocus state. Through the special influences of light on the view regions of human eyes, the growth of the ocular axis can be effectively controlled, which achieves the characteristics of good and fast prevention and treatment of myopia and hyperopia.