An optical lens including a first lens group and a second lens group is provided. The first lens group is arranged between a magnified side and a minified side. The first lens group includes a lens closest to the magnified side. A refractive power of the lens is negative, and at least one surface of the lens is an aspherical surface. The second lens group is arranged between the first lens group and the minified side. A distance between the first lens group and the second lens group is smaller than 0.7 millimeter. The optical lens is complied with conditions of 0.53