Our goal was the evaluation of the effect of polymorphic loci and other factors on milk performance and the technological properties of cow´s milk. DGAT1, LEP, FASN, SCD1, CSN2, CSN3 and LGB genes were analysed. The DGAT1 AA genotype was associated with higher milk, protein and fat yields. In CSN3, the AA genotype was associated with a heigh milk yield, and BB genotype with a high protein content. Also in other genes, some significant associations with milk productivity were found. The alleles did not affected significantly the technological quality. In CSN2 gene, BB genotype had the best alcohol test, and the worst renneting, A1A1 genotype had the best milk fermentation ability. CSN3 genotypes affected the technological quality significantly, BB genotype positively, and genotypes with alleles A and E negatively. The essential importance of farms on milk yield, composition and technological quality was found, so effect of polymorphisms was somewhat blurred. The use of DGAT1 and CSN3 polymorphisms in the breeding is recommended.