A projection lens disposed between an enlarged side and a reduced side and including a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having positive refractive power, and an optical element disposed between the second and the third lens groups is provided. The first lens group includes a first and a second lens sequentially arranged from the enlarged side to the reduced side and respectively having a positive and a negative refractive power. The second lens group between the first lens group and the reduced side includes a third, a fourth, a fifth, and a sixth lens sequentially arranged from the enlarged side to the reduced side. The fifth and the sixth lens respectively have a positive refractive power. The third lens group disposed between the second lens group and the reduced side includes a seventh lens.