A zoom lens includes three lens groups. The first lens group from the object side has negative refractive power and is formed of one or two lens components. The second lens group from the object side has positive refractive power and is formed of one lens component. The third lens group from the object side has negative refractive power, is formed of one lens component, and is moveable for focusing. Both the second and third lens groups move for zooming. A stop is arranged in the second lens group on the object side thereof. Two lens surfaces of each lens group are aspheric. Each lens component may be a lens element and all lens elements may be made of plastic. The zoom lens may be formed of only the three lens groups and satisfies specified conditions to assure that the zoom lens is small, lightweight, and favorably corrects various aberrations.