The invention provides a method for predicting noise in a wind power plant. The method comprises the steps that 1, an apparent sound power level database and a meteorological data database of a wind turbine generator in the wind power plant are established; 2, an equivalent discharging sound power level of the wind turbine generator is obtained; 3, a wind power plant sound pressure level, relative to a sound source measuring receiving point, of the wind power plant is obtained. Compared with the prior art, the method for predicting noise in the wind power plant can conduct real-time and long-period noise prediction on the wind power plant based on the geographical characteristics of the wind power plant.