Background Secondary peritonitis is associated with high rates of morbidity and mortality. Data on the effect of staged re-laparotomy or re-laparoscopy as a surgical option in the management of abdominal sepsis due to secondary peritonitis are limited and conflicting. Herein, we report the outcomes of patients undergoing staged peritoneal lavage (SPL) for secondary peritonitis in our department. Methods This is a single-center retrospective analysis of the data of patients undergoing SPL for secondary peritonitis. SPL was performed via either re-laparotomy or re-laparoscopy. The simplified acute physiology score (SAPS II) was calculated at the time of the initial operation and for each SPL. The end points of interest included: the evolution of sepsis characterized by the SAPS II score, the mortality rate and the rate of definitive abdominal wall closure. Results The data of 74 patients with a median age of 73 years requiring at least one SPL between 2012 and 2019 were analyzed. The median number of SPL performed was three (range 1-12). A sequential drop of SAPS II score from 41 at the initial procedure to 32 at the third SPL was documented. The overall mortality rate was 16.2%, definitive abdominal closure was achieved in all surviving patients and the median length of stay was 17.5d Conclusion Staged re-laparotomy or re-laparoscopy with peritoneal lavage may reduce the severity of peritonitis and reduce the risk of mortality in patients with abdominal sepsis. Maintaining the abdominal wall under constant retraction using a rigid mesh while creating an open abdomen is a crucial step in achieving definite abdominal wall closure. Thus, staged peritoneal lavage may be a good surgical option for selected patients with peritonitis.