Bariatric surgery (BS) is known to improve the components of metabolic syndrome (MS) in obese patients. However, few studies have evaluated the impact of bariatric surgery versus medical therapy (MT) in patients with MS, especially in patients with low body mass index (BMI). This study aimed to assess the effect of bariatric surgery on MS in patients with low BMI by comparing BS (BMI\<35 kg/m2 and BMI≥35 kg/m2) with MT (BMI\<35 kg/m2). A retrospective study including patients with MS undergoing bariatric surgery and medical therapy at a single institution. We follow up the 5 years effect of bariatric surgery versus medical therapy on the remission of MS, its individual components, atherosclerotic cardiovascular disease (ASCVD) risk, and medication used.