Background: Many of the beneficial metabolic effects of bariatric surgery have been attributed to altered peptide hormone profiles, especially involving pancreatic and gut peptides. We aimed to assess the impact of sleeve gastrectomy (SG), one anastomosis gastric bypass (OAGB), and sleeve gastrectomy with loop bipartition (SGLB) on gastrointestinal tract hormones. Methods: A case series analysis was carried out at our institution from February 2018 to February 2021. This study included 3 groups subjected to different operations; each group consisted of 50 patients. Results: This study included 132 women (88%) and 18 men (12%). Mean age in SG, OAGB and SGLB were 33.5 SD3.89, 30.9 SD7.2, and 40.3 SD6.89 respectively. The percentage of change in Peptide YY levels two weeks postoperatively in SG, OAGB, and SGLB were 29.1%, 40.1%, and 65.6% respectively. In Glucagonlike peptide-1 were 19.3%, 34.1% and 32.8% respectively. However, the percent of change in Ghrelin level two weeks were 36.5%, 50%, and 50.6% respectively. Finally, the percent change in secretin hormone levels were 61.5%, 56.9%, and 46.3% respectively. Conclusions: Differences in gastrointestinal hormones that regulate energy and glucose homeostasis are a possible mechanism for more significant weight loss after SGLB and OAGB compared to SG.