The hydrogen bonded complexes between carbonyl bases and hydroxylic derivatives have been extensively studied by infrared spectrometry; by comparison very little Raman data have been reported in the literature. Some qualitative measurements on thevC=Oband of acetone dissolved in water-tetrachloride mixtures have been performed by Singurel1. Quantitative data on the absolute Raman intensity have been obtained for complexes involving cyclohexanone2, acetone, acetophenone3and methylacetate4. For these systems, hydrogen bond formation brings about a moderate intensity enhancement of thevC=Oband. In this work the Raman intensity of thevC=Oband of ethylformate (EtFo) complexed with phenol derivatives is investigated.