Introduction <p>Laparoscopic sleeve gastrectomy (LSG) is a widely performed bariatric procedure, known for its efficacy in weight reduction and metabolic improvement. Postoperative development or exacerbation of gastroesophageal reflux disease (GERD) and its impact on esophageal motility remain areas of concern. This study aimed to assess the impact of GERD on esophageal motility in patients undergoing LSG and associated predictors using multivariate analysis.</p> Setting <p>King Abdullah Medical City, Makkah, Saudi Arabia.</p> Methods <p>A retrospective, record-based cohort study was conducted on 600 patients who underwent LSG, with inclusion criteria requiring availability of both preoperative and postoperative high-resolution manometry (HRM) and documented GERD status. Sociodemographic, clinical, endoscopic, and manometric data were analyzed using descriptive and inferential statistics, including multivariate logistic regression.</p> Results <p>Postoperative GERD symptoms were prevalent across all age groups, especially in younger patients and smokers, though no significant associations were found with gender, comorbidities, or preoperative proton pump inhibitors (PPI) use. While most patients exhibited normal peristalsis and esophageal motility post-surgery, ineffective peristalsis and mild motility disorders were observed more frequently in those with GERD. Multivariate analysis identified preoperative GERD (OR = 3.20, <i>p</i> = 0.032), postoperative GERD (OR = 2.85, <i>p</i> = 0.041), and limited BMI reduction or postoperative weight gain as significant predictors of esophageal motility disorders.</p> Conclusion <p>GERD, both pre- and postoperatively, significantly increases the risk of esophageal motility dysfunction after LSG. Suboptimal weight loss further contributes to this risk, emphasizing the need for comprehensive preoperative evaluation and long-term follow-up to optimize outcomes.</p>