Objective: To analyze the prescription patterns for the treatment of ulcerative colitis (UC) and to investigate factors co-occurring with systemic corticosteroid use. Methods: We used patient-level data from Korean National Health Insurance claims database to identify patients diagnosed with UC (ICD-10 code : K51) and their medications prescribed for UC between January 1 and Decemeber 31, 2017. We found that medications for UC treatment were 5-aminosalicylic acid (5-ASA), immunomodulators, biologics, and corticosteroids. We presented the prescription pattern according to the sex, age group, type of health insurance, site of UC, type of medical institution, and concomitant medication. To evaluate factors associated with prescription of systemic corticosteroids for UC, we used a multivariate logistic regression model to estimate adjusted odds ratios (aORs) and their 95% confidence intervals (CIs). Results: Of 1,469 UC patients, 74.5% used 5-ASA and 15.2% used systemic corticosteroids. 5-ASA constituted 77.5% of all prescriptions and systemic corticosteroids accounted for 13.1%. The most widely used therapy was 5-ASA monotherapy (54.8%), followed by a double therapy with 5-ASA and immunomodulators (8.2%) or 5-ASA and systemic corticosteroids (7.2%). Systemic corticosteroids were more likely to be prescribed with immunomodulators (aOR=1.88, 95% CI=1.54- 2.28) and biologics (aOR=2.82, 95% CI=2.28-3.50) than without them. Conclusions We found that 15.2% of UC patients were prescribed with a systemic corticosteroid, which is less than reported previously. Systemic corticosteroids were more likely to be prescribed with immunomodulators and biologics.