The present invention discloses a system for speed error compensation. A predetermined speed signal subtracts a feedback speed signal to generate a speed error signal, and a microprocessor receives the speed error signal and outputs a calculated result. A feedback controller receives the calculated result and generates a first tracking control effort signal. A feedforward controller receives the speed error signal and generates a second tracking control effort signal according to a DC steady state error in the speed error signal. An optical head module moves at an actual speed determined by the total of the first tracking control effort signal and the second tracking control effort signal. A gain controller generates the feedback speed signal according to an actual speed signal detecting from the actual speed.