A total of 15 broiler chickens was fed with a diet of wheat/wheat gluten supplemented with lysine on three N-intake levels (I: 1,500; II: 2,100; III: 3,000 mgN/LW0, 67kg) between their 11th and 20th day of life and tested with regard to the characteristic data of N-metabolisation (N-balance experiment) and 15N-incorporation in selected tissues and the complete body of the chickens. While N-metabolisation did not show any differences of procedure, the results of 15N-incorporation indicated slightly more favourable utilisation conditions for synthetic lysine in III in the complete body and the liver. One can derive from the results that the level of feed intake cannot be excluded as one variable in the utilisation of synthetic lysine, the problems in connection with this, however, cannot completely be explained with this. For the restrictions of N-intake effective in the N-balance experiment no negative influence is to be expected with regard to the utilisation of synthetic lysine in comparison to ad libitum feeding.