Chronic constipation is one of the most common complaints among children. It is a cause of about 3% visits in paediatric outpatient clinic. The problem, which is often belittled, is an unpleasant and persistent complaint for both child and its family. The causes of constipation may be both organic and non-organic. Among non-organic problems, the most important is probably the chronic retention of faeces, which is made by incorrect hygienic habits, incorrect diet, and insufficient physical activity. The problem often appears when child’s environment changes, for example when child goes to kindergarten or school, which are the places where child for different reasons prevents from defecating. However, to make the final diagnosis, the organic causes should be definitely rejected, because they require causal treatment. Treatment of the most common functional constipation needs complex pharmacological and non-pharmacological methods. The therapy of constipation is usually long. The aim of therapy is to consolidate such model of defecation when child regularly deposits soft faeces without unpleasant pain. Extremely important is also a psychological support for whole family, often absorbed in difficult child’s problem. To achieve the therapeutic success a patient and conscientious cooperation between doctor and patient and his family is required, because positive and permanent effects of treatment are reached after a relatively long time.