The study of some genetic parameters involvement in cattle selection was carried out on the breeding „Agro-Maiac JLC”LTD on a herd of 228 cows. Variability, heritability, repeatability, correlation and regression characters of selection were studied. It was established that variation in milk production is 16,6%, the amount of fat on lactation 17,0% and 10,6% body mass .The content of milk fat varies less than 2,9%. Heritability coefficient of milk production is 0,546, fat content 0,464 and total fat 0,788 per lactation. Repeatability of milk production per lactation varies between 0,546 and 0,883, milk fat content between 0,0 and 0,50 , total fat per lactation between 0,522 and 0,821 and between 0,074 and 0,322 body weight. High positive relation was established between milk production per lactation (+0,245 +0,993) from weak to average between body weight and milk production (+0,176 +0,431). Conclusion is that the genetic parameters must be used in selection work.