A process for preparing 4-hydroxybutyl acrylate by transesterifying an alkyl acrylate with 1,4-butanediol in the presence of a dialkyltin oxide such that each of the alkyl groups has 4 to 8 carbon atoms, characterized in that the amount of the dialkyltin oxide is adjusted to 0.00001 to 0.01 moles per one mole of the alkyl acrylate.
