PURPOSE: Sepsis and severe sepsis are the most common cause of death among critically ill patients admitted in medical intensive care units. As more than one-third of the adult population of the United States is obese; we undertook a systematic review of the association between obesity and mortality among patients admitted with sepsis, severe sepsis, or septic shock. MATERIALS AND METHODS: A systematic review was conducted to identify pertinent studies using a comprehensive search strategy. Studies reporting mortality in obese patients admitted with sepsis were identified. RESULTS: Our initial search identified 183 studies of which 7 studies met our inclusion criteria. Three studies reported no significant association between obesity and mortality, 1 study observed increased mortality among obese patients, whereas 3 studies found lower mortality among obese patients. CONCLUSION: Our review of the current clinical evidence of association of obesity with sepsis mortality revealed mixed results. Clinicians are faced with a number of challenges while managing obese patients with sepsis and should be mindful of the impact of obesity on antibiotics administration, fluid resuscitation, and ventilator management. Further studies are needed to elicit the impact of obesity on mortality in patients with sepsis.