The invention discloses a method for determining heat storage capacity in a wind power heating system. The method comprises the steps that a day wind power output curve and a daily electricity load curve in a preset time period are acquired; a time period with small wind power output and larger daily electricity load in the preset time period is acquired according to the day wind power output curve and the daily electricity load curve; heat storage capacity required by a heat storage device in the wind power heating system is acquired according to heating energy consumption of the time period with small wind power output and larger electricity load. According to the method, the time period with small wind power output and larger electricity load in the preset time period is acquired according to the day wind power output curve and the daily electricity load curve, and the required capacity of the heat storage device is determined according to the heating requirement in the time period. Actual changes of wind power output and electricity load in the preset time period are comprehensively considered, the required capacity of the heat storage device is determined, waste of the capacity is avoided while the operation requirement of the wind power heating system is met, and the cost of the wind power heating system is reduced.