Milk contain essential nutrient which play role in the human body. While the price of the milk is depend on milk yield and milk compositions. The present study was conduct on the lactating cross bred Holstein Friesian cows. The purpose of the study is to identifying the effect of age, parity and stage of lactation on the milk yield and major milk compositions (milk protein, milk fat, lactose, water, solid not fat, dry matter) and also the milk fat and milk protein ratio. The milk samples were collected from each of the cows according to lactation period. The milk samples were analysed by different methods that is Kjeldahl method for milk protein analysis; Rose-Gottlied method for milk fat analysis; Colorimeter Picric Acid method for lactose analysis; over dry method for dry matter analysis. The milk protein percentage are shown significant (P<0.05) was lower in advancing age when compared to the Group (age 3-4 years) and Group (age 5-6 years) during early and mid lactation stage. The milk protein percentage, Solid not fat percentage and milk yield are higher at the early lactation stage, then decreased during mid lactation stage. The suitable milk fat and milk protein ratio was found in Group (age 3-4 years) and Group (parity 3) both also in mid stage of lactation. This study was indicated that the effect of stage of lactation, age and parity has effect on milk yield, milk composition and milk fat and milk protein ratio.