A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power. A distance between consecutive lens units of the first through fourth lens units varies for zooming. The first lens unit includes, in order from the object side to the image side, a negative lens and a positive lens whose surface on the object side has a convex shape. In the zoom lens, a focal length f1, a focal length f3, an Abbe number υd1p, a focal length f3i, and an Abbe number υd3i are appropriately set.