Proteins were extracted and separated by SDS-PAGE from leaves of scions and rootstocks of differentVitiscultivars. Banding patterns were used to identify the different cultivars after extraction of the proteins with a medium containing Tris-HCI (0.68 M, pH 7.8), SDS (2%),β-mercaptoethanol (5%), glycerol (10%) and PEG 20 000 (2%). Electrophoretogram formulae using relative band mobility and staining intensity of the different bands were calculated for the different cultivars. No differences in Rm values were found between individual scion or rootstock cultivars but the technique can be used to distinguish between scion and rootstock cultivars.