ISSR-PCR markers were used to assess genetic diversity and to elucidate relatedness among 21 Ukrainian and 3 West European sweet cherry varieties, which are widely cultivated in Ukraine. The discriminatory potential was tested for 11 ISSR-PCR primers, which produced 193 amplicons. UBC 835, 836, 841 and 881 were identified as the best primers suitable for routine application. The studied cultivars appear to be genetically highly heterogenic and can be divided in two main groups. The first one includes closely related cultivars obtained by hybridization of Drogan’s Yellow (Drogans gelbe Knorpelkirsche), Valerii Chkalov and some other forms. The second group comprises less similar cultivars derived from several West-European and unknown ancestors. Origin of several Ukrainian cultivars is discussed.