The serum amino acids profile in ten severe burn patients was basically similar with the findings in major burns reported in our proceeding article, supporting the conclusion that burn patients might have a particular amino acid pattern. The larger was the burn size, the more severe was the nitrogen loss. Following a severe burn, the patient was faced with the challenge of acute protein malnutrition. After severe burns, the ratio of serum Phe/Tyr rose to a higher level than in the major burns. Moreover, the elevation of serum Met/Cys ratio indicated a more serious metabolic disturbance. During the first two weeks postburn, acute decrease of serum BCAA by 20-30 per cent of the normal value was associated with a striking increase of mortality. This fact indicated the level of BCAA might be of prognostic value. In severe burns, other than huge amount of calories and protein supplied, enriched BCAA, and perhaps, carnitine might be beneficial.