A lens module includes a barrel and at least one lens. The barrel defines a through hole bounded by an inner circumference surface thereof. The inner circumference surface includes at least one first circumference latching surface. The at least one lens includes at least one second circumference latching surface corresponding to the at least one first circumference latching surface. One of the first circumference latching surface and the corresponding second circumference latching surface is a ring-shaped concave surface, and the other is a ring-shaped convex surface latchable with the ring-shaped concave surface.