This study aims to evaluate the clinical and radiological efficacy as well as safety profiles of Anbainuo, a recombinant human TNFRII:Fc fusion protein, combined with methotrexate (MTX) versus MTX alone or Anbainuo alone in the treatment of Chinese patients with moderate to severe rheumatoid arthritis (RA). In this 24-week, multicenter, double-blind, active comparator-controlled study, 396 RA patients were randomized into combination therapy group (Anbainuo plus MTX), Anbainuo group, or MTX group. Clinical response was assessed using the American College of Rheumatology (ACR)-N, ACR20, ACR50, ACR70, and van der Heijde modification of Sharp score, among which ACR-N and ACR20 were defined as primary major endpoints. After 24 weeks of treatment, the ACR-N in the combination therapy group (12.79 ± 9.24 %) was significantly higher than that in Anbainuo group (9.56 ± 11.16 %) and in MTX group (5.08 ± 11.1 %) (p = 0.00 and p = 0.00, respectively). Patients in Anbainuo group had significantly higher ACR-N than those in MTX group (p = 0.02). More patients in the combination therapy group (53.6 %) achieved ACR50 improvement response than those in the MTX group (30.8 %). ACR70 of combination therapy group (27.7 %) was significantly higher than that of Anbainuo group (15.8 %) and MTX group (7.70 %), with no significant difference between Anbainuo group and MTX group. DAS28-ESR in the combination therapy group was significantly reduced compared to either monotherapy groups. Moreover, DAS28-ESR was significantly lower in Anbainou group than in MTX group. The combination therapy group also showed significantly less radiographic progression than the MTX group (p = 0.03). The total adverse events (AE) in the combination group (40.9 %) was significantly higher than those in the MTX group (28.8 %) (p < 0.05). Anbainuo combined with MTX therapy can effectively control the disease activity and radiographic progression of RA, while the incidence of AE also increased compared to either Anbainuo or MTX.