Allergic purpura in children is mostly caused by allergens or immune complexes. It is mainly manifested by bleeding and inflammation of skin, intestines, joints and small renal vessels. It is also clinically known as Henoch-Sch?nlein purpura (HSP) or IgA vasculitis. If it is not treated in time, it will aggravate the condition of children, and may cause gastrointestinal tract, kidney and other organs damage in children, which will have a serious impact on children's life safety. The main clinical treatment methods are drugs and blood purification, of which anti-inflammatory drugs, antihistamines and immunosuppressive drug are the main drug treatment, and blood purification mainly includes plasma exchange and blood perfusion. This article analyzes the pathogenesis of allergic purpura in children, and discusses the related treatment strategies and clinical application effects, aiming to provide a basis for the diagnosis and treatment of the disease.