Objective: to compare the improvements in lipid profile in patients undergoing sleeve gastrectomy (SG) and Rouxen-Y gastric bypass (RYGB). Methods: in a mixed cohort study, we evaluated 334 patients undergoing SG and 178 patients undergoing RYGB at the University Hospital of the Federal University of Pernambuco and at the Real Hospital Português de Beneficência, Recife, PE, Brazil. We measured serum levels of total cholesterol, LDL, HDL and triglycerides preoperatively and at three, six, 12 and 24 months follow-up. Results: the SG group consisted of 58 men and 276 women. In the group submitted to RYGB, there were 64 men and 114 women. The mean age was 37.2±20.5 years in the SG group and 41.9±11.1 years in the RYGB group. The preoperative mean BMI was 39.4±2.6kg/m 2 and 42.7±5.8kg/m 2 for the SG and RYGB groups, respectively. In the preoperative period, 80% of the patients had at least one abnormality in the lipid profile. Two years after surgery, there was improvement in total cholesterol, LDL, HDL and triglycerides in the group submitted to RYGB. In the group submitted to SG, after two years there was improvement in total cholesterol, HDL and triglyceride levels. Conclusion: both techniques resulted in improvements in the lipid profile, but the RYGB was more effective. LiraAnalysis of the lipid profile of patients submitted to sleeve gastrectomy and Roux-en-Y gastric bypass. 2 Rev Col Bras Cir 45(6):e1967 Lira Analysis of the lipid profile of patients submitted to sleeve gastrectomy and Roux-en-Y gastric bypass. 4 Rev Col Bras Cir 45(6):e1967