A projection lens consists essentially of a first lens group having positive refractive power and a second lens group having positive refractive power in this order from a magnification side. A surface closest to a reduction side in the first lens group is convex. The second lens group consists of two single lenses each having positive refractive power, and in each of which a surface having a smaller absolute value faces the reduction side. Further, the following conditional expressions (1) through (4) are satisfied: |R1b/R1f|≦0.5  (1); |R2b/R2f|≦0.6  (2); |Δ/f2|≦0.3  (3) and d2/f2≦0.4  (4).