The purpose of the present invention is to provide a method, whereby, in the dry fractionation of an oil or fat, a decrease in solid-liquid separation efficiency, said decrease being caused by the engulfment of a filtrate fraction into a crystal fraction after crystallization and press filtration, can be prevented and thus the crystal slurry can be efficiently separated after the crystallization. A method for the dry fractionation of an oil or fat, said method comprising, before or after crystallization, adding a definite amount of a filtration aid followed by mixing and then press-filtering the thus obtained crystal slurry. Thus, the crystal slurry can be easily separated into a crystal fraction with little engulfment of a liquid fraction and the liquid fraction.