Provided are an optical pointing apparatus and an automatic gain control (AGC) method thereof. The optical pointing apparatus includes: an image sensor comprised of a plurality of pixels, for receiving light reflected by a work surface, sensing image data, and outputting an electrical signal; an automatic gain control (AGC) unit for receiving the electrical signal, controlling the gain of the electrical signal according to brightness and darkness from images of the work surface and the motion speed of the optical pointing apparatus, and outputting a gain output signal; and an image data processor for receiving the gain output signal, analyzing brightness and darkness from images of the work surface to control the gain of the electrical signal, detecting the motion speed of the optical pointing apparatus to control the gain of the electrical signal, and calculating and outputting the motion speed of the optical pointing apparatus.