A camera and a lens module are provided. The camera includes a lens module and an image sensor. The lens module includes a lens unit including a protrusion, the lens unit being configured to move in a direction of an optical axis of the camera. The lens module further includes a movement guide including an inclination part, the protrusion being configured to slide along the inclination part while the lens unit moves in the direction of the optical axis. The lens module further includes a driver configured to drive the lens unit in the direction of the optical axis, and a pre-loader configured to provide a pre-load between the lens unit and the movement guide in the direction of the optical axis.