Obesity is a major public health issue. Surgery is the most effective treatment to obtain weight loss, stabilize weight status and decrease comorbidities. Yet post-operative complications can be serious and their treatment can also be a real challenge. The low invasive nature of endoscopy makes it an alternative to surgery. It can be used to diagnose and treat digestive hemorrhage, ulcers, stenosis, anastomotic leakage or fistula. This article aims to review the different bariatric surgical techniques, complications and their specific endoscopic treatment options.