Biologics are increasingly used to treat Vogt-Koyanagi-Harada disease, but head-to-head comparisons with conventional immunosuppressants are lacking. Here in this randomized trial (Chinese Clinical Trial Registry, ChiCTR2100043061), we assigned 110 patients (27 early-phase and 83 late-phase) to cyclosporine-based immunosuppressant strategy (N= 56) or adalimumab-based biologic strategy (N= 54), each combined with a modified corticosteroid regimen. The primary outcome is change from baseline in best-corrected visual acuity at week 26. The margin of non-inferiority for cyclosporine is −7 letters. The primary outcome is 11.2 letters (95% CI, 7.5 to 14.9) in the cyclosporine group and 6.3 letters (95% CI, 3.1 to 9.6) in the adalimumab group (difference, 4.9; 95% CI, 0.2 to 9.5;P< 0.001 for non-inferiority). The between-group difference is −0.8 letters (95% CI, −6.1 to 4.5) in early-phase disease and 5.7 letters (95% CI, 0.2 to 11.2) in late-phase. Serious adverse events are reported less frequently in the cyclosporine group than in the adalimumab group (0.70 vs. 1.21 events per patient-year). Here, we report that combined with a non-standard corticosteroid regimen, cyclosporine-based immunosuppressant strategy is non-inferior to adalimumab-based biologic strategy by 26 weeks for visual improvement in a cohort of patients with Vogt-Koyanagi-Harada disease, 75% of whom have a late-phase disease.