This study aimed to systematically review existing evidence on the preoperative use of GLP-1 receptor agonists (GLP-1 RA) before metabolic and bariatric surgery (MBS). Web of Science, Embase, PubMed, and Scopus were searched systematically with relevant keywords for articles on the effect of preoperative GLP-1 RA use on MBS outcomes. Eleven observational studies evaluated the effects of preoperative GLP-1 RAs. GLP-1 RAs enhance preoperative weight loss with earlier optimization for MBS. Preoperative use of these agents were associated with increased postoperative nausea but showed no significant differences in the rate of major complications or readmissions. Benefits included improved diabetes outcomes, although findings on postoperative weight loss were inconsistent, and some studies reported higher surgical adhesion rates. More robust evidence is needed to guide the incorporation of GLP-1 RAs into preoperative pathways for MBS.