Context: The efficacy of tocilizumab (TCZ) in treating Graves orbitopathy (GO) remains uncertain due to the small sample sizes of earlier studies, and there is a lack of research on the drug for juvenile GO. Objective: To evaluate the effectiveness of TCZ in treating GO that is resistant to conventional therapy. Design: This observational study at a tertiary care center included 79 Chinese GO patients, 15 of whom were pediatric patients, with 52 of these patients having moderate to severe active GO (all adult patients having steroid-resistant GO). Intravenous infusion of TCZ 8 mg/kg was given every 28 days for 4 months. Changes from baseline in visual acuity (VA), intraocular pressure (IOP), proptosis, clinical activity score (CAS), and thyrotropin receptor antibody (TRAb) levels throughout TCZ therapy were assessed at baseline (T0), the fifth month (T4), and follow-up (T5). Additionally, improvements in CAS by at least 2 points and CAS < 4 points at T4 and T5 were evaluated. Results: Significant improvements were found in VA, IOP, proptosis, CAS, and TRAb levels in the adult group, and proptosis in the pediatric group at T5 (P < .05). Additionally, significant improvements were identified in TRAb levels and CAS (active GO at T0) in the pediatric group at T4 (P < .05). In the adult and pediatric group with active GO at T5, 71.4% and 60% experienced a decrease in CAS by >= 2 points, respectively; 89.3% and 60% achieved the response criterion of low activity disease (CAS < 4 points), respectively. Conclusion: TCZ emerged as a valuable therapeutic option for Chinese patients with active, corticosteroid-resistant, moderate to severe GO.