The invention provides an analyzing method and apparatus for system frequency-regulation capacity. The analyzing method comprises the steps of obtaining predicated load data according to historical load data and annual load growth factor; obtaining predicated wind power data according to wind power data and annual load growth factor; and calculating to obtain the system frequency-regulation capacity according to the predicated wind power data and the predicated load data. Through the analyzing method for the system frequency-regulation capacity provided by the invention, the frequency-regulation capacity of future systems including wind power can be predicated effectively based on the existing known wind power parameters.