Severe acute pancreatitis (SAP) is one of the most common critical illnesses clinically. Although great achievements have been made through total rehydration and active anti-infection in the early stage of the disease, the treatment outcome is still not satisfactory when infected pancreatic necrosis occurs in the later stage. With the rapid development of the concept of minimal invasiveness, the step-up strategy has gradually replaced the strategy of open debridement and achieved good therapeutic results. However, because of the individual differences of patients and the diversity of treatment methods, there is still no uniform standard for current treatment plans. In recent years, the step-up strategy will be further improved under the guidance of the emerging micro-non-invasive concept. This article introduces the current status of this strategy in treatment of SAP, and provides guidance and evidence for its surgical treatment.