The invention discloses a calculating method for an equivalent sound level A of any point in a transformer substation sound field. The method is characterized in that any point in the transformer substation sound field is defined as a point O, n main transformers are arranged in a transformer substation, and are marked as the main transformers i respectively, and the distance between the point O and the main transformers i in the transformer substation is Xi, and the equivalent sound level A Li (A) generated in the point O of the main transformers i is equal to aXi<3>+bXi<2>+cXi+di; the equivalent sound level A of any point O in the transformer substation sound field is specified in the specification. According to the method, the calculation result can accurately reflect the attenuation situation of noise of a large-scale power transformer along with the distance in the actual running, influences of effects including ground attenuation, air absorption and the like are comprehensively considered, and the calculation of the equivalent sound level A, including factory bound noise, of any point in the transformer substation sound field is rapid, accurate and close to the reality of production.