Obesity and obesity-related diseases may emerge as a major public health issue in the near future. There are several effective methods to prevent obesity, such as diet, sports, and pharmacotherapy. However, these methods provide temporary weight loss. Bariatric surgery, which has become widespread in recent years, stands out as a method for providing permanent weight loss in obesity treatment. Bariatric surgery not only restricts the volume of the stomach and limits calorie intake but also provides weight-controlled weight loss in the long term. It is considered the most effective treatment method for addressing diseases such as hypertension and diabetes accompanying obesity. Due to its success in preventing obesity, it is a frequently preferred surgical method today. In the postoperative period of this method, potential complications following other surgical interventions that are specific to this method can be observed. Early postoperative complications include bleeding, atelectasis, venous thromboembolism, anastomotic leakage, and rhabdomyolysis. On the other side, late postoperative complications include dumping syndrome, marginal ulcers, and nutritional and vitamin deficiencies. Prevention, early diagnosis, and treatment of these complications are essential for the success of bariatric surgery to prevent morbidity and mortality. This review discusses complications commonly encountered in the postoperative period, nutritional problems, and the importance of patient follow-up in individuals undergoing bariatric surgery.