Background & Objective:Obesity has become a serious health problem that has become increasingly important in recent years. Since patients with high levels of obesity have dyslipidemia and an unbalanced lipid profile, they have a high risk of both diabetes mellitus and cardiovascular disease. This study aimed to evaluate the short (3 months) and long term (12 months) effects of mini-gastric bypass surgery from the current bariatric surgical techniques on the lipid profile.Methods:Of the patients undergoing Mini-gastric bypass operation between January 2016 to December 2018 at the General Surgery Clinic of Private Samsun Büyük Anadolu Hospital, demographic data and changes in lipid concentrations at 3 and 12 months were analyzed. Patients were grouped according to age, sex, body mass index (BMI), cardiologic risk groups, bypass lengths, and obesity classes. Total cholesterol, triglyceride, LDL-cholesterol, and HDL cholesterol values of the patients were examined at the time of admission to the outpatient clinic before the operation, at the postoperative third month and at the post-operative twelfth-month. Patients who did not go for a checkup during the one-year follow-up and whose data could not be reached or missing were excluded from the study.Results:There was no significant difference in terms of age, sex, and cardiovascular risk (p> 0.05). Although the HDL-C level was initially low (p <0.001), it significantly increased 12 months after surgical treatment (p <0.001). While serum concentrations of LDL cholesterol, total cholesterol, and triglycerides were high preoperatively, they significantly decreased at 12 months postoperatively (p <0.001). When compared with values in the 3rd- and 12th-month, there was a significant decrease in the class-3 obesity group but not in the class-2 obesity group. When serum HDL cholesterol concentrations were compared with preoperative baseline and postoperative 12th-month those, no statistically-significant difference was found in serum concentrations in the 3rd month, although there was a significant increase in both class 2 and 3 obesity groups.Conclusion:In patients undergoing mini-gastric bypass surgery, serum LDL cholesterol, total cholesterol, and triglyceride concentrations decreased in the 12th postoperative month, but serum HDL cholesterol concentrations increased.