Background: This study compared the efficacy and safety of fluticasone propionate (FP) inhalation n solution with budesonide (BUD) suspension for inhalation administered via nebulizer, in Chinese adult patients with severe, persistent asthma. Methods: This was a multicenter, randomized, active-controlled, single-blind, parallel-group study, conducted at 26 clinical sites in China. Participants were randomized 1: 1 to FP nebules 1 mg twice daily or BUD 2 mg twice daily via nebulizer for 12 weeks. Results: A total of 317 adult patients were randomized. The primary endpoint was mean change in morning peak expiratory flow (PEF) over weeks 1-12 from baseline, and analyzed in the ITT (n=315) and PP populations (n=283). Week 12 PEF increase from baseline was 26.7 L/min (14.1%) and 28.0 L/min (15.3%) in the ITT population, and 29.1 L/min (15.7%) and 30.1 L/min (16.2%) in the PP population, in the FP and BUD groups, respectively; all improvements were of clinical significance. Lower limits of the two-sided 95% CIs for the least squares (LS) mean treatment difference (FP minus BUD) were -12.19 L/min (ITT) and -12.95 L/min (PP), both above the pre-specified non-inferiority criteria -12.00 L/min and not clinically meaningful. There was no significant difference in the week 12 mean FEV1 increase between the FP and BUD groups (0.237 L/16.79% vs. 0.236 L/17.73%). Lower limits of the 95% CIs for LS mean treatment difference in morning PEF change from baseline over weeks 1-4 in a post hoc analysis were -10.41 and -11.96 L/min in the ITT and PP populations respectively; both above -12.00 L/min. A review of safety data indicated that rates of AEs, SAEs, and drug-related AEs were similar between two groups. Conclusions: The 12-week treatment of FP inhalation solution administered via nebulizer is safe and effectively for treating severe, persistent asthma in Chinese patients over 12 week.