Severe acute pancreatitis (SAP) leads to numerous inflammatory and nutritional disturbances. All SAP patients are at a high nutritional risk. It has been proven that proper nutrition significantly reduces mortality rate and the incidence of the infectious complications in SAP patients. According to the literature, early (started within 24-48 h) enteral nutrition (EN) is optimal in most patients. EN protects gut barrier function because it decreases gastrointestinal dysmotility secondary to pancreatic inflammation. Currently, the role of parenteral nutrition (PN) in SAP patients is limited to patients in whom EN is not possible or contraindicated. Early versus delayed EN, nasogastric versus nasojejunal tube for EN, EN versus PN in SAP patients and the role of immunonutrition (IN) in SAP patients are discussed in this review.