The invention provides a method and device for judging abnormal wind speed data, and the method comprises the steps: obtaining historical wind speed data in a preset time period according to a presettime interval, and calculating a first difference value between the historical wind speed data of adjacent time points; segmenting the historical wind speed data and the first differential value respectively, and counting the distribution number of the historical wind speed data in each differential segment in each wind speed segment; obtaining a predetermined number of to-be-measured wind speed data according to the predetermined time interval, and calculating a second differential value between the to-be-measured wind speed data at adjacent time points; calculating an average value of absolute values of second differential values calculated for all to-be-measured wind speed data; based on the number of the historical wind speed data distributed in each difference subsection in each windspeed section corresponding to each piece of to-be-measured wind speed data, calculating a difference threshold value; and if the calculated average value is greater than the difference threshold, determining that the predetermined number of to-be-measured wind speed data is abnormal wind speed data.