Process for preparing 1,1,4,4-tetraalkoxybut-2-ene derivatives of the general formula (I), where the radicals R1 and R2 are each, independently of one another, hydrogen, C1-C6-alkyl, C6-C12-aryl, such as phenyl, or C5-C12-cycloalkyl or R1 and R2 together with the double bond to which they are bound form a C6-C12-aryl radical, such as phenyl, a phenyl radical substituted by one or more C1-C6-alkyl groups, halogen atoms or alkoxy groups or a monounsaturated or polyunsaturated C5-C12-cycloalkyl radical, R3, R4 are each, independently of one another, hydrogen, methyl, trifluoromethyl or nitrile, which comprises electrochemically oxidizing 1,4-dialkoxy-1,3-butadiene of the formula II where the radicals R1, R3 and R4 have the same meanings as in the formula I, in the presence of a C1-C6-alkyl alcohol.