Objective: The aim of this study was to determine the clinical presentation and severity of ulcerative colitis (UC) in Pakistani adult patients. Materials and methods: An observational study. Data were obtained by reviewing the medical records of patients who visited a gastroenterology clinic between 2008 and 2012. Results: There were 54 patients diagnosed as UC. The male to female ratio was 1:1. Mean age at diagnosis of UC was 38.7 ± 11.8 years (median 36.5, range 18–64). The predominant presenting symptoms were mucus diarrhea in 49 (90.7%), gross blood in stools in 42 (77.8%), abdominal pain or cramps in 40 (74.1%) and weight loss in 15 (27.7%). Left-sided colitis was present in 23 (42.6%), pancolitis in 15 (27.8%), extensive colitis in 11 (20.4%), and proctitis in five (9.2%). The severity of UC as judged by the Mayo scoring system showed that 68.5% were suffering from moderate to severe disease while 31.5% had mild disease. The extra-intestinal manifestation were found only in seven patients; arthritis in five patients and anterior uveitis in two patients. The arthritis was unilateral and the sites were knee joint in three patients and sacroiliac joint in two patients. Conclusion: Ulcerative colitis presents in our adult patients may present at any age with no gender preponderance. The disease severity is moderate to severe in the majority of patients and more than half of them have left-sided colitis or pancolitis at the time of presentation. Extraintestinal manifestations were not common.