In a process for producing alkoxybutenes, 1,3-butadiene or a butadiene-containing hydrocarbon mixture is reacted with an alcohol of formula ROH (I) at an increased temperature and pressure in the presence of a Brönsted acid, yielding a mixture of addition products of formulas (II) and (III), in which the radical R is a C2-C20 alkyl, alkenyl, cycloalkyl or cycloalkenyl group substituted or not with 1 to 2 C1-C10 alkoxy or hydroxy groups, or is a C2-C10 aryl or C7-C11 aralkyl group or a methyl group. The disclosed improvement consists in that the reaction is carried out in the presence of water.