Ensuring the required level of complete protein and amino acids in the rations is necessary for good growth, health and high productivity of poultry. Knowing the levels of protein and amino acids in feed components and the need of broiler chickens for individual amino acids, it is possible to regulate protein nutrition targetedly at the level of individual amino acids and improve the amino acid profile of the ration. In broiler chicken feeding, valine is the fourth limiting amino acid after methionine, lysine and threonine. At the poultry farm of Yaroslavsky Broiler JSC, a study was conducted to assess the effect of adding synthetic valine to the main feeding ration on the zootechnical performance of broiler chickens and production profitability. In the control group, the diet included 3 limiting amino acids - lysine, methionine and threonine. In the experimental group, the diet included 4 limiting amino acids - lysine, methionine, threonine and valine, observing the valine balance. When chickens were raised on diets with valine (4 limiting amino acids supplemented), the average chicken live weight, feed conversion, total live weight and meat yield were better than in the control group receiving a diet without valine (3 limiting amino acids). Also, in the experimental group, less amount feed was expended, and the productivity index was higher than in the control group.