A camera module consists of an image sensor, an objective lens system, and a lens drive mechanism. The objective lens system includes a taking lens and a prism having a reflection surface inclined at an angle of 45° to an optical axis of the taking lens, to reflect incident light toward the image sensor on a circuit board, which is positioned in parallel to the optical axis of the taking lens. The lens drive mechanism includes a motor and a rotary shaft driven by the motor. The motor is positioned behind the prism, and a drive shaft of the motor is coupled to the rotary shaft through a power transmission mechanism. The rotary shaft is positioned on one radial side of the taking lens and is coupled to a movable lens element of the taking lens such that the movable lens element is moved in the axial direction by rotary motion of the rotary shaft.