A pitch control apparatus for controlling the pitch value for a wind power generation system includes a generator comparing unit that calculates an error signal based on a difference between a generator measurement signal corresponding with an operation of the power generation system and a generator reference signal, and a reference pitch calculating unit that calculates a reference pitch value using the error signal. The pitch control apparatus further includes a compensation pitch calculating unit that calculates a compensation pitch value using an error value from the wind power generation system and a pitch calculating unit that calculates a pitch value using the reference pitch value and the compensation pitch value. The error value may be any one of a voltage error value from a direct-current capacitor, a voltage error value from a grid connection point, a speed error value from a rotor, and a frequency error value from a grid connection point.