Precise evaluation of the parental forms? genetic variation is the base of rational, modern breeding. DNA patterns obtained in ISSR (inter simple sequence repeat) reactions for 24 strawberry cultivars, frequently used in the crossing programme at the Research Institute of Pomology and Floriculture, were analysed. Diversifying genotypes, polymorphic DNA products were observed in reactions with 54 out of 90 tested primers (806-896, #9 UBC). Six primers (811-814, 824, 840) generating 44 polymorphic bands with length from 270 to 2030 bp allowed to diversify all investigated cultivars. The DNA profiles characterising each of genotypes contained 10-19 polymorphic ISSR products.