Background: Anemia is a common extra-intestinal manifestation of inflammatory bowel disease. The magnitude of anemia in Inflammatory Bowel Disease (IBD) patients and the risk factors were not previously studied from Saudi Arabia. Objectives: Objectives of the study were to find prevalence of anemia, etiology and its risk factors. Design: Retrospective cohort study Setting: Hospitalized patients at King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia Patients and methods: The data pertaining to anemia was collected from IBD patients between 2000 to 2018, at the time of first presentation to the hospital, and the lowest hemoglobin during the follow up. Anemia was diagnosed if hemoglobin (Hb) level was below 13 g/dl in males and below 12 g/dl in females. Severe anemia was defined as Hb <10 g/dl for both genders. Patients were further classified into iron deficiency anemia, Anemia of Chronic Disease (ACD), based on c-reactive protein and serum ferritin levels. Vitamin B12 deficiency was diagnosed if the vitamin B12 level was <150 pg /ml. Main outcome measures: Prevalence of anemia, etiology and its risk factors in IBD patients Results: From 190 patients IBD screened, 109 patients were included, 56% were males. Crohn's disease was in 77 (70.6%) and ulcerative colitis in 32 patients (29.4%) At the time of first presentation to the hospital, 51.4% of patients had anemia, and during the median follow-up of 759 days, 62.4% of our cohort were diagnosed with severe anemia. Iron deficiency anemia was diagnosed in 13.8%, ACD was diagnosed in 3.7%, and iron deficiency plus ACD was diagnosed in 2.8%. From 101 patients, 26 of them (23.9%) had vitamin B-12 deficiency. No identifiable risk factors were found at the time of presentation for anemia in IBD population. Binary logistic regression analysis showed female gender (p-value 0.001) and anemia at presentation (p-value 0.0001) were risks for subsequent development of severe anemia. Conclusion: Anemia in IBD population is highly prevalent. Female gender and anemia at presentation are risks for the development of severe anemia in IBD population. Limitations: Hospital based retrospective study.