Diverticular disease it is one from the most common disease, and the number of young people with this illness is increasing last time. It is connected with our life style: without physical activity and low-fiber diet. Main symptoms of diverticular disease can be mild (like: abdominal pain, flatulence, constipations or diarrhea) but can also be connected with serious complications (like perforation or bleeding). The aim of this article was assigning the rules of diagnostics and treatment both mild and severe causes of this illness. Methods of prevention were also presented.