A projection zoom lens includes a front lens group, a rear lens group, and an aperture stop. The front lens group has negative refractive power and is disposed adjacent to an object side of the projection zoom lens. The front lens group includes a first lens group, a second lens group, and a third lens group. The rear lens group has positive refractive power and is disposed adjacent to an image side of the projection zoom lens. The rear lens group includes a fourth lens group, a fifth lens group, and a sixth lens group. The aperture stop is disposed between the front lens group and the rear lens group. The third lens group, the fourth lens group, and the fifth lens group move along an optical axis of the projection zoom lens to change an effective focal length of the projection zoom lens when the projection zoom lens zooms.