The utility model discloses a digital imaging lens which is compact in structure, and comprises a main lens cone and a lens mechanism arranged in the main lens cone, wherein the lens mechanism comprises a first lens, a second lens, a third lens and a fourth lens in sequence; the first lens is positioned at one end of the lens mechanism, which is close to an object; a space ring is arranged between the first lens and the second lens; and a diaphragm space ring is positioned between the third lens and the fourth lens. The digital imaging lens is compact in structure and small in volume; the structure of an adjusting screw is adopted, so that the concentricity of an optical system can be guaranteed; a spacing between the first lens and the second lens can be guaranteed by one space ring, so that the spacing accuracy among the lenses can be improved, and the volume of the whole lens is reduced; and each lens is provided with a glue injecting hole, so that after injected glue, the digital imaging lens can be more firmly fixed, and strong in shock resistance.