Abstract: Persistent inflammation-immunosuppression-catabolism syndrome (PICS) is a clinical syndrome in patients surviving from severe trauma or sepsis, which is characterized by prolonged stays in intensive care unit, persistent inflammation response, immune suppression, high protein catabolism, and high mortality. This article aims to review the proposed process of the concept, the mechanism, the clinical features, and the diagnosis and treatment progress of PICS, which is helpful for further understanding pathogenesis and pathophysiological mechanism of PICS in patients with severe burns and improving clinical curative efficacy and prognosis of patients with severe burns.