Ulcerative colitis (UC) is an inflammatory bowel disease that can affect the entire colon or just one part of it. Chronic inflammation causes ulcers in the intestine and prevents the normal functioning of the large intestine, whose main role is the absorption of water from the digestive contents and the retention of feces. Due to the disruption of these physiological processes, the clinical picture of ulcerative colitis develops, which includes diarrhea with sanies several times a day, general weakness of the body, malnutrition and unintentional weight loss. The exact cause of this disease is still unknown, but it is believed that due to an error in the function of the mucous layer of the intestinal wall, there is a disorder in immunoregulation and the patient's immune system recognizes its own colon as foreign. The diagnosis of ulcerative colitis is extensive because it primarily requires the exclusion of all possible factors that may cause similar symptoms. In addition, a colon endoscopy and X-ray should be performed. Each of these diagnostic tests does not have great diagnostic significance in itself, however, by collecting all the data obtained from the tests and in combination with the patient's medical history, a timely and adequate diagnosis can be established. As the cause of the disease itself is still unknown, pharmacological treatment consists of groups of drugs that help alleviate the symptoms of the disease. It is also possible to surgically remove the part of the colon affected by colitis in order for the patient to completely get rid of the symptoms of the disease. Nutrition plays an essential role in preventing the development of ulcerative colitis symptoms and maintaining remission, however its mechanism of action remains unknown. This paper will thoroughly discuss the anatomy and physiology of the colon, the pathogenesis of ulcerative colitis, the clinical picture, epidemiological data and methods of diagnosis and therapy. All of these aspects are necessary for a complete and clear understanding of the disease and the patient’s needs. The aim of this paper is to review the relevant scientific and professional literature to summarize all the important knowledge and knowledge regarding ulcerative colitis, care for those suffering from this disease and ways to educate patients about the condition.