BACKGROUND/AIMS: Tofacitinib and upadacitinib are small-molecule compounds that inhibit the Janus kinase pathway for the treatment of refractory ulcerative colitis. Only a few reports have compared the efficacy and safety of these 2 drugs in real-world practice. We aimed to show our real-world evidence of these drugs and compare the efficacy and safety profiles in the treatment of ulcerative colitis. METHODS: This study is a single-center retrospective analysis. Patients treated with tofacitinib or upadacitinib at our hospital between June 2018 and January 2024 who were monitored for 24 weeks were included. The primary outcome was steroid-free clinical remission at 24 weeks. Secondary outcomes were response and remission rates at each time point, time series changes in partial Mayo scores and laboratory results, treatment survival at 24 weeks, and the incidence of adverse events. RESULTS: A total of 68 patients treated with tofacitinib and 34 patients treated with upadacitinib were included. Steroid-free clinical remission rate at 24 weeks was significantly higher in upadacitinib-treated patients than in tofacitinibtreated patients (64.7% vs. 38.2%). The response rates in upadacitinib-treated patients exceeded 60% after 8 weeks of treatment through to 24 weeks, and the rates were higher than those in tofacitinib-treated patients. The incidences of adverse events were 79.4% in upadacitinib-treated patients and 38.2% in tofacitinib-treated patients. The most common adverse event was acne for upadacitinib. CONCLUSIONS: Upadacitinib was more effective than tofacitinib in inducing remission in ulcerative colitis patients. The incidence of adverse events was significantly higher with upadacitinib than tofacitinib.