Abstract: Complicated intra-abdominal infections (cIAIs) are common clinical conditions but difficult to manage in abdominal surgical practice. Since usually combined with gastrointestinal dysfunction, nutritional support therapy plays a key role in the long-term treatment. Early enteral nutrition could maintain intestinal barrier function, regulate immune function, and reduce gut permeability and bacterial translocation. Enteral combined with supplement parenteral nutrition could provide full-energy support to improve negative nitrogen balance and physiological function. Underlying pathophysiological changes should be understood, and appropriate mode of nutritional support should be chose carefully during disease course which can reduce incidence of complications and improve patients′ prognoses.