A camera module includes a lens barrel, a lens holder, and a focusing spring. The lens barrel includes an operation plate and a first body, and the outer diameter of the operation plate exceeds that of the first body, thereby a staging surface is formed facing the first body. The first body includes an outer surface, and defines an external thread on the outer surface. The lens holder includes a second body, and defining a second receiving hole therethrough. The second body includes an upper surface and an inner surface, and defines an internal thread on the inner surface. The lens barrel is received in the second receiving hole, and the external thread of the lens barrel is screwed and meshed with the internal thread of the lens holder. The focusing spring is compressively interposed between the staging surface and the upper surface.