The present invention relates to the use of alkoxylated polyglycerols preparable by polycondensation of glycerol and subsequent alkoxylation for demulsifying water-oil emulsions, in particular in the production of crude oil from crude oil/water emulsions. The invention provides for the use of alkoxylated polyglycerols with a molecular weight of from 250 to 100,000 units which comprise 2 to 100 glycerol units whose free OH groups are alkoxylated with C2-C4-alkylene oxide groups or a mixture of such alkylene oxide groups so that the alkoxylated polyglycerol has a degree of alkoxylation of from 1 to 100 alkylene oxide units per free OH group. The alkoxylated polyglycerols of the present invention are employed for demulsifying oil/water emulsions in amounts of from 0.0001 to 5% by weight, based on the oil content of the emulsion to be demulsified.