Semaglutide, a novel glucagon-like peptide-1 receptor agonist, has transformed the therapeutic landscape for type 2 diabetes mellitus. However, its effect on osteoclast activity and its potential to induce weight-related muscle loss raises concerns about its impact on spine surgery outcomes. As such, evaluating semaglutide's influence on transforaminal lumbar interbody fusion (TLIF) is imperative, given the procedure's reliance on successful bony fusion to prevent postoperative instability and further interventions. Using an all-payer database (MARINER), the authors analyzed data from patients with type 2 diabetes mellitus who were 18-74 years of age and who underwent short-segment fusion (≤ 3-level) TLIFs between January 2018 and October 2022. Patients were either exposed to semaglutide or not. A comprehensive 1:3 (exposure vs no exposure) matching was performed based on age, sex, obesity, hypertension, coronary artery disease, chronic kidney disease, smoking status, osteoporosis, levels of surgery, and basal-bolus insulin dependence. Kaplan-Meier survival curves and log-rank testing were performed to study the probability of additional lumbar fusion surgery within 1 year. After the 1:3 matching, 1781 patients were identified, with 447 in the semaglutide-exposed cohort and 1334 in the nonexposed cohort. Most patients in both groups were 55-69 years old, and 59.3% were female. Analysis showed that the likelihood of undergoing additional lumbar fusion surgery within 1 year post-TLIF was significantly higher in the semaglutide-exposed group than in the nonexposed group (OR 11.79, 95% CI 8.17-17.33). Kaplan-Meier plots and log-rank testing further confirmed a statistically significant divergent probability in the need for additional surgery within 1 year between the cohorts (log-rank, p < 0.001). Semaglutide exposure appears to be associated with a higher likelihood of additional lumbar fusion surgeries within 1 year post-TLIF, especially in patients receiving the medication for longer durations. Although the mechanisms remain speculative, potential impacts on bone turnover and the onset of muscle loss may be contributory factors. Further research is needed to elucidate the exact mechanisms and to develop strategies for optimizing surgical outcomes in these patients.