Cyclosporine or infliximab (IFX) have been used to avoid surgery in patients with severe refractory ulcerative colitis (UC). Tacrolimus (Tac) is occasionally used as an alternative to cyclosporine; however, the comparative efficacy of Tac and IFX has not been reported. We aimed to compare the effectiveness of Tac and IFX in hospitalized patients with UC. In a propensity score-matched cohort derived from a large nationwide database, 4-year effectiveness was compared between patients initiated on Tac and those initiated on IFX. The primary outcome was the colectomy rate during the index hospitalization. We also analyzed the cumulative medication discontinuation, UC-related rehospitalization, and colectomy rates after discharge. Among 29,239 hospitalized patients, 4,565 were extracted for eligibility, of whom 2,170 were treated with Tac and the remaining 2,395 with IFX. After propensity score matching, 1,787 patients were selected for each group. During the index hospitalization, excluding patients who switched to another molecular-targeted agent, the colectomy rate was higher in the Tac group than in the IFX group (7.8% vs 4.2%, P < 0.01). Among patients discharged without colectomy, the cumulative medication discontinuation (28.4% vs 17.1%, P < 0.01) and rehospitalization (22.4% vs 15.4%, P < 0.01) rates were higher in the Tac group than in the IFX group; however, there was no difference in the cumulative colectomy rate (3.3% vs 2.7%). Although Tac and IFX were effective for avoiding surgery in hospitalized patients with UC, IFX was more effective than Tac. IFX also had higher long-term effectiveness. Future prospective studies comparing the efficacy of Tac and IFX are warranted.