The invention relates to a method for separating acetone from acetone/water mixtures, according to which a partial flow of the acetone/water mixture is concentrated in a column operating under positive pressure in order to obtain a product with an acetone concentration of at least 80 wt. %, and a partial flow of the acetone/water mixture is concentrated in a column operating under normal pressure. The top product from the column operated under positive pressure is used to heat the bottom product of the column operated under normal pressure, by means of a heat exchanger, and the top product is then introduced into the column operated under normal pressure, above the supply of the partial flow of the acetone/water mixture. This method allows the specific energy demand for acetone separation to be significantly reduced, thereby presenting considerable cost advantages. The invention also relates to a device for carrying out such a method.