The embodiment of the invention provides a shadow evaluation method, device and system for a wind power plant. The shadow evaluation method comprises the steps that the meteorological information of the wind power plant is obtained; and whether shadow is generated by wind power generation units of the wind power plant or not is judged according to the meteorological information of the wind power plant. According to the shadow evaluation method for the wind power plant, whether shadow is generated by the wind power generation units in the wind power plant or not is judged according to the meteorological information of the wind power plant, and the judgment result, based on the comprehensive meteorological information of the wind power plant, of the shadow flicker effect is more accurate and more credible, so that subsequent further evaluation of the influence range of the shadow flicker effect is facilitated, and the negative influences of the shadow flicker effect on surrounding potential objects can be reduced easily.