In tuo axperiments diets containing animal protein and with normal (17%) or lowered to 14% and 11% crude protein contant were fed during 6 month to Leghorn hens. Low-protein diets were used alone or with a supplement of methionine or methionine and lysine. Reduction of the dietary protein level to 14% did not affect laying performance. Methionine improved egg production and feed and protein conversion for eggs on low-protein diet but methionine and lysine added together were not efficient. Significant decrease of laying performance has been noted when the dietary protein level was reduced to 11%. Enrichment of low-protein diet with methionine and lysine added together improwed egg production and feed conversion in hens.