A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power. In the zoom lens, during zooming, each lens unit is configured to move such that distances among the lens units vary. The first lens unit consists of three lenses. A relative partial dispersion θgF and an Abbe number νd of a material of the positive lens included in the first lens unit are appropriately set by satisfying predetermined mathematical conditions.