Background: Posterior spinal fusion is performed for severe adolescent idiopathic scoliosis (AIS), with bone graft playing a critical role in achieving solid fusion. Iliac crest bone graft (ICBG) is the gold standard but has donor site morbidity, leading to increased use of non-ICBG. This study compared the effectiveness and safety of ICBG and non-ICBG bone grafts in AIS. Methods: This meta-analysis included 23 studies with 3,350 patients, categorized into ICBG and non-ICBG groups. The primary outcome was fusion rate; secondary outcomes were implant-related complication rate, infection rate, donor site pain, blood loss, and operation time. A proportion meta-analysis was conducted to estimate binary outcomes, and a weighted mean model was used to estimate continuous variables. Results: The fusion rate was 97% (95% confidence interval [CI], 93-99) in ICBG group and 97% (95% CI, 95-98) in non-ICBG group. Implant-related complications occurred in 5% (95% CI, 3-7) and 4% (95% CI, 2-6) of each group, while surgical site infections occurred in 3% (95% CI, 2-7) and 2% (95% CI, 1-3). Donor site pain was observed exclusively in ICBG group, with a prevalence of 49% (95% CI, 3–97). Estimated pooled blood loss was 1,461.10 mL (95% CI, 545.30-2,376.90) in ICBG group and 1,047.45 mL (95% CI, 666.92-1,427.99) in non-ICBG group. The estimated pooled operation time was 246.77 (95% CI, 221.74-271.80) and 232.37 (95% CI, 194.88-269.86) for each group. Conclusions Considering both ICBG and non-ICBG demonstrated high fusion rates and low complication rates, non-ICBG grafts may serve as an effective and safe alternative to ICBG, minimizing morbidity, donor site pain, and blood loss.