Idiopathic thrombocytopenic purpura (ITP) is the most common autoimmune blood disorder and the most common thrombocytopenia in children. ITP is the result of accelerated destruction of antibody-coated platelets by phagocytic cells, mainly in the spleen. ITP can be clinically classified into two major forms. The acute form is usually seen in children between the ages of 2 and 10, equally in both sexes. Mostly there is a history of preceding viral upper respiratory tract infection, or immunization. A seasonal incidence, in the winter and spring months, can be seen. About 80% of children with acute ITP have an excellent outcome with complete recovery. A duration of more than 6 months defines the chronic form. Children who develop chronic ITP are more often females aged over 10 years. No seasonal fluctuation is observed. Over a period of years following diagnosis, 30 to 80% of children with chronic ITP recover completely. Most children with ITP have mild bleeding symptoms. Treatment is usually not necessary. The commonly used regimens are corticosteroids and intravenous immunoglobulin. So far, there is no evidence that pharmacotherapy can prevent a chronic course of the disease.