INTRODUCTION: The term inflammatory bowel disease is a common name for chronic inflammation of the gastrointestinal system. According to the older classification, they are divided into Crohn's disease and ulcerative colitis, while according to the newer classification, new forms of the illness are added, namely indeterminate colitis and "pouchitis" (inflammation in the mucous membrane of the pouch occurred during the treatment of ulcerative colitis). The inflammation was caused by the cellular immune response of the gastrointestinal mucosa, but the exact cause is unknown. Neither the existence of a specific infectious factor nor environmental and nutritional factors has been confirmed. Immunological reactions include the release of inflammatory mediators such as cytokines, interleukins, and tumor necrosis factor. Inflammatory bowel diseases occur in people of all age groups, but most often in population younger than 30 years old. They can lead to a significant reduce in the quality of life, and it is assumed that patients are exposed to an increased risk of depression and anxiety. Symptoms vary from mild to very severe and can develop gradually or suddenly. Diagnostic tests that are used are digitorectal examination, colonoscopy, and tests for occult bleeding. Diseases are treated with medication and surgery. The drugs used are aminosalicylates, immunomodulators, corticosteroids and antibiotics. Regular controls and medical examinations are extremely important. Nurses play an important role in the multidisciplinary treatment of inflammatory bowel diseases. OBJECTIVE: The plan of this work is to show a similarity of the quantity of men and women ordeal from inflammatory bowel illness in the Zadar General Hospital (gastroenterology clinic) in the period from 2019 to 2021. years. It also shows the incidence and prevalence of Crohn's disease and ulcerative colitis in Europe and North America and the rate of these illness in the pediatric people. MATERIALS AND METHODS: Over the formation of this paper, statistical data obtained from the information system of the OB Zadar will be used. Statistical data presented on the pages of Journal of Crohn's and Colitis, National Library of Medicine and Digestive Medicine Research were also used. THE RESULTS: This work collected statistics on the number of men and women newly diagnosed with Crohn's disease and ulcerative colitis in Zadar General Hospital. The total number of newly recognized men with Crohn's disease and ulcerative colitis in 2019 was 23, 23 in 2020, and 11 in 2021. The total number of newly diagnosed women with Crohn's disease and ulcerative colitis in 2019 was 30, in 2020 13, and 15 in 2021. Data on the frequency of illness in Europe and North America were also collected, together with statistics on the incidence of the disease in the pediatric population in European countries. CONCLUSION: Inflammatory bowel diseases are illness described by periodic part of inflammation of the gastrointestinal tract. They consist of two idiopathic diseases: Crohn's disease and ulcerative colitis. Both diseases have a genetic predisposition, are incurable and cause enormous morbidity. The highest rate of incidence and frequency is in Europe and North America, and in the last few years it has also been increasing in Asia, where until now the frequency was very low. In pediatrics, inflammatory bowel diseases have become the most frequently diagnosed childhood disease.