The invention discloses a rotating speed tracking object optimizing method capable of achieving maximizing wind energy capturing efficiency of a wind machine. The rotating speed tracking object optimizing method comprises the following steps that smoothing processing for the optimum rotating speed is conducted through a first order digital filter, and real-time searching for the filter coefficient is conducted, so that a rotating speed tracking object is optimized. According to the rotating speed tracking object optimizing method capable of achieving the maximizing wind energy capturing efficiency of the wind machine, the rotating speed tracking object of the wind machine is optimized, the problem that the rotating speed is hard to be rapidly and precisely adjusted according to the quick-changed wind speed signal by the wind machine with large rotary inertia under the limited-range electric generator electromagnetic torque controlling effect is solved, and the wind energy capturing efficiency of the wind machine is further improved.