An optical mouse apparatus includes a light source circuit, a sensing circuit, and a processing circuit. The light source circuit is used for generating and emitting a light signal onto a surface so as to generate a light reflected signal. The sensing circuit is used for estimating an image offset of the optical mouse apparatus. The processing circuit is coupled to the light source circuit and the sensing circuit and used for generating and outputting a control signal to a terminal according to the image offset outputted by the sensing circuit. The sensing circuit is further used for detecting at least one of a moving speed or an offset direction of the image offset of the optical mouse apparatus, so as to dynamically determine whether to compress data of the image offset outputted to the processing circuit, for reducing data amount read by the processing circuit.