Laparoscopic Roux-en-Y gastric bypass (LRYGB) still remains the gold-standard bariatric procedure. Short-term weight loss and improvement of type 2 diabetes mellitus (DM2) after LRYGB are well-documented. Little data are available on long-term weight loss and continued remission of DM2 in these patients. This study reports on weight loss and remission of DM2 in 576 consecutive patients who underwent primary LRYGB between August 2001 and August 2009 with at least 10-year follow up. All patients were treated at a single institution by a single surgeon. All data were collected and entered into the database prospectively. A total of 576 patients were included in the study. Patients' mean age was 38.2 ± 10.9 years and females represented 88.2% of patients. Patients' ethnicity was diverse, including African Americans (44.4%), Caucasians (34.0%), Hispanics (18.1%), and 3.5% from other backgrounds. On average, there were 6.9 ± 2.7 comorbidities per patient and DM2 was initially present in 150/576 patients (26.0%). Mean preoperative weight and BMI were 132.4 ± 22.0 kg and 48.3 ± 6.7 kg/m2, respectively. Ten-year follow-up reporting rate was 145/576 (25.2%). Maximum weight loss occurred at 18 months (mean weight 83.4 ± 16.5 kg, mean BMI 30.5 ± kg/m2). At 10 years, mean weight was maintained at 94.8 ± 20.5 kg and mean BMI was 34.3 ± 6.8 kg/m2. The average weight regain between one and ten years was 8.27 kg. Among patients with preoperative DM2, continued remission of DM2 at 10 years occurred in 19/32 (59.4%) patients. LRYGB provides durable long-term weight loss, as well as successful remission of DM2 at 10 years. More long-term follow-up studies evaluating weight loss and comorbidities extending beyond the initial 10-year period are needed. Such studies are essential for projecting late outcomes of LRYGB, particularly in younger patients with life expectancy exceeding several decades. © 2020. Springer Science+Business Media, LLC, part of Springer Nature.