Background. Liver cirrhosis affects the results of many of the traditional techniques currently used to evaluate nutritional status. Our aim was to compare the traditional two-compartment model (subjective global assessment and anthropometry and blood tests) of nutritional assessment with a multicompartmental model (body composition analysis) in patients with cirrhosis. Methods. Seventy-nine patients and 17 control subjects were studied. Subjective global assessment, anthropometry and blood tests, and body composition analysis were performed for each. The two most important compartments were body cell mass and total body fat. The subjects were classified by each method as well nourished or moderately or severely malnourished. Results. Twenty-five patients (31.6%) were malnourished according to the subjective global assessment, 2 (6.3%) with Child’s class A cirrhosis, 10 (34.5%) with class B, and 13 (72.2%) with class C, whereas 24 (30.4%) were malnourished according to the traditional model, 5 (15.6%) in the Child’s A group, 8 (27.6%) in B, and 11 (61.1%) in C. According to the multicompartmental model, 48 patients (60.1%)were malnourished, 11 (34.4%) in Child’s A, 20 (69%) in B, and 17 (94.4%) in C. The use of the multicompartmental model increased the prevalence of malnutrition by more than 60%in Child’s classes A and B patients and by more than 20%in Child’s class C patients. Conclusions. Traditional nutritional assessment, although easier, underestimated the prevalence and severity of malnutrition in patients with cirrhosis. The underestimation was more pronounced in Child’s class A and B patients. Background. Liver cirrhosis affects the results of many of the traditional techniques currently used to assess nutritional status. Our aim was to compare the traditional two-compartment model (subjective global assessment and anthropometry and blood tests) of nutritional assessment with a multicompartmental model (body Seventy-nine patients and 17 control subjects were studied. Subjective global assessment, anthropometry and blood tests, and body composition analysis were performed for each. The two most important compartments were body cell mass and total Body fat. The subjects were classified by each method as well nourished or moderately or severely malnourished. Results. Twenty-five patients (31.6%) were malnourished according to the subjective global assessment, 2 (6.3%) with Child’s class A cirrhosis, 10 (34.5%) with class B, and 13 (72.2%) with class C, whereas 24 (30.4%) were malnourished according to the traditional 48 (60.1%) were malnourished, 11 (34.4%) in the Child’s A group, 8 (27.6%) in B, and 11 in Child’s A, 20 (69%) in B, and 17 (94.4%) in C. The use of the multicompartmental model increased the prevalence of malnutrition by more than 60% in Child’s classes A and B patients and by more than 20% in Child’s class C patients. Conclusions. Traditional nutritional assessment, although easier, underestimated the prevalence and severity of malnutrition in patients with cirrhosis. The underestimation was more pronounced in Child’s class A and B patients.