To provide a zoom lens having excellent optical performance over the whole image screen while miniaturizing the whole lens system and being suitable for a liquid crystal projector by constituting the zoom lens of five lens groups as a whole, adopting a negative lead type as a lens type, and properly constituting the respective lens groups.

In an almost telecentric zoom lens, this zoom lens has five lens groups of a first group of negative refractive power, a second group of positive refractive power, a third group of fixed negative refractive power, a fourth group of positive refractive power and a fifth group of positive refractive power in order from the conjugate point side having a long distance, and power is varied by moving these second/fourth groups. When varying power to a focal distance on the telescopic end from a focal distance on the wide angle end, the second lens group and the fourth lens group move to the conjugate side having a long distance. When a focal distance of the whole system on the wide angle end is denoted by fw, a focal distance of the whole system on the telescopic end is denoted by ft, a focal distance of the first lens group is denoted by f1 and a focal distance of the second lens group is denoted by f2, (1.0<f1/f2<3) and a condition of an expression are satisfied.