This study was conducted to identify gene polymorphisms and to investigate the relationships of polymorphisms with yield and composition of milk from Holstein cows. Significant relationships of growth hormone (GH), leptin (LEP) and myogenic factor 5 (MYF5) gene polymorphisms with 305-day milk yield were observed (P < 0.01). Signal transducers and activators of transcription 5A (STAT5A) gene polymorphism did not show any significant relationships with investigated traits (P > 0.05). With regard to the 305-day milk yield, GH-LV, LEP-AA and AB and MYF5-GG genotypes were found to be superior over the other genotypes. It was concluded based on present findings that GH, LEP and MYF5 genes could be used as candidate genes for milk yield of Holstein cows.