Objective: Acute exacerbations are the most frequent cause of medical visits, hospitalizations, admissions and death among patients with chronic obstructive pulmonary disease (COPD). Our objective was to investigate the effects of a high-fat low-carbohydrate (CHO) diet on the prognosis of patients hospitalized for an acute exacerbation of COPD. Material and Methods: Thirty male patients with COPD, hospitalized for acute exacerbation were randomized into two groups. Standard hospital diet was administered to group I for 10 days and an experimental diet comprising of 50% standard hospital diet and 50% of a special enteral product containing high-fat low-CHO was administered to group II Pulmonary function tests, anthropometric measurements and blood gas analysis were per-formed on the first and tenth days of the study. All patients completed a questionnaire regarding socio-economic status and nutritional habits. Results: Pulmonary function tests revealed statistically significant differences in tidal volume (TV) and forced vital capacity (FVC) between the measurements of day I and day 10 of the two groups with better results in group 11 (p< 0.05). There was no significant difference between groups on blood gas analysis parameters on days 1, 3,5,7, and 9 (p> 0.05), yet there was an improvement (increase in PaO2, decrease in PaCO2). Conclusion: A high-fat low-CHO diet can improve the prognosis of COPD patients with acute exacerbation. Since nutritional interventions can improve treatment outcomes and quality of life in COPD patients, multi-center studies with a larger sample size and long-term nutrition support are needed.