An optical lens, comprising: a front lens group (1, 2), configured to diverge incident light rays; and a rear lens group (3, 4, 5, 6), configured to converge the divergent incident light rays, the material of the front lens group being plastic and the material of the rear lens group being plastic or glass; wherein the front lens group comprises a first lens and a second lens; the rear lens group comprises a third lens, a fourth lens, a fifth lens and a sixth lens; and the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens are sequentially arranged from an object side to an image side, the material of the first lens, the second lens, the third lens, the fourth lens and the sixth lens being plastic and the material of the fifth lens being plastic or glass; characterized in that the first lens has a meniscus shape convex toward the object side, a first surface and a second surface of the first lens being both aspheric surfaces; the second lens has a cylindrical biconvex shape, a first surface and a second surface of the second lens being both aspheric surfaces; the third lens has a biconvex shape, a first surface and a second surface of the third lens being both aspheric surfaces; the fourth lens has a biconcave shape, a first surface and a second surface of the fourth lens being both aspheric surfaces; the fifth lens has a biconvex shape, a first surface and a second surface of the fifth lens being both spherical surfaces; and the sixth lens has a concave-plane shape, a first surface of the sixth lens being an aspheric surface and a second surface of the sixth lens being a planar surface. a front lens group (1, 2), configured to diverge incident light rays; and a rear lens group (3, 4, 5, 6), configured to converge the divergent incident light rays, the material of the front lens group being plastic and the material of the rear lens group being plastic or glass; wherein the front lens group comprises a first lens and a second lens; the rear lens group comprises a third lens, a fourth lens, a fifth lens and a sixth lens; and the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens are sequentially arranged from an object side to an image side, the material of the first lens, the second lens, the third lens, the fourth lens and the sixth lens being plastic and the material of the fifth lens being plastic or glass; characterized in that the first lens has a meniscus shape convex toward the object side, a first surface and a second surface of the first lens being both aspheric surfaces; the second lens has a cylindrical biconvex shape, a first surface and a second surface of the second lens being both aspheric surfaces; the third lens has a biconvex shape, a first surface and a second surface of the third lens being both aspheric surfaces; the fourth lens has a biconcave shape, a first surface and a second surface of the fourth lens being both aspheric surfaces; the fifth lens has a biconvex shape, a first surface and a second surface of the fifth lens being both spherical surfaces; and the sixth lens has a concave-plane shape, a first surface of the sixth lens being an aspheric surface and a second surface of the sixth lens being a planar surface.