Bariatric surgery is an effective strategy for blood pressure (BP) reduction, but most of the evidence relies on office BP measurements. In this study, we evaluated the impact of bariatric surgery on 24-hour BP profile, BP variability, and resistant hypertension prevalence. This is a randomized trial including obese patients with grade 1 and 2 using at least 2 antihypertensive drugs at maximal doses or >2 at moderate doses. Patients were allocated to either Roux-en-Y Gastric Bypass (RYGB) combined with medical therapy or medical therapy alone for 12 months. The primary outcome was the 24-hour BP profile and variability (average real variability of daytime and night time BP). We evaluated the nondipping status and prevalence of resistant hypertension as secondary end points. We included 100 patients (76% female, body mass index, 36.9±2.7 kg/m ² ). The 24-hour BP profile (including nondipping status) was similar after 12 months, but the RYGB group required less antihypertensive classes as compared to the medical therapy alone (0 [0–1] versus 3 [2.5–4] classes; P <0.01). The average real variability of systolic nighttime BP was lower after RYGB as compared to medical therapy (between-group difference, −1.63; 95% CI, −2.91 to −0.36; P =0.01). Prevalence of resistant hypertension was similar at baseline (RYGB, 10% versus MT, 16%; P =0.38), but it was significantly lower in the RYGB at 12 months (0% versus 14.9%; P <0.001). In conclusion, RYGB significantly reduced antihypertensive medications while promoting similar 24-hour BP profile and nondipping status. Interestingly, bariatric surgery improved BP variability and may decrease the burden of resistant hypertension associated with obesity. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01784848.