The nature of allergic purpura is an allergic vascular inflammation that can cause lesions in multiple areas such as the skin, joints, and internal organs, and the vast majority of cases can be associated with renal involvement, i.e., allergic purpura nephritis, which is one of the common causes of renal involvement in pediatric systemic disorders. The prognosis of allergic purpura depends mainly on the involvement of the kidneys and its extent, so it is necessary to increase the awareness of these diseases to ensure that children and their families adhere to long-term follow-up and regular treatment. Children often have a history of infection or exposure to specific foods or medications prior to the onset of the disease, and soon develop a rash, abdominal pain or arthralgia, and some children develop hematuria and proteinuria suggesting renal involvement. The majority of children have purpura-like rash as the first symptom, which typically presents as purpura of different sizes, slightly above the skin surface, and does not fade when pressed, mostly symmetrically distributed on both lower limbs; however, some atypical cases have recurrent abdominal pain as the first symptom, which is difficult to diagnose clearly before the rash appears, and can be easily misdiagnosed as surgical emergency abdomen, so we should be alert. The diagnosis of allergic purpura is not difficult according to the typical clinical manifestations, but some children with renal involvement need to have renal aspiration biopsy to clarify the pathological diagnosis and guide the treatment. Allergic purpura needs to be differentiated from thrombocytopenic purpura, the rash of both have similarities, but the latter with thrombocytopenia is easy to distinguish between the two. In addition, allergic purpura needs to be differentiated from other immune diseases that can have multisystem involvement, and serum immunologic tests including some autoantibodies are important in this case. There is no specific treatment for allergic purpura, the possible allergens should be found and removed as much as possible, gastrointestinal symptoms can be treated with symptomatic antispasmodic therapy, adrenal corticosteroids are helpful to relieve joint and gastrointestinal symptoms and can be applied for a short time. The prognosis of allergic purpura is greatly related to the degree of renal lesions, therefore, special attention should be paid to the early detection of renal damage in allergic purpura, and timely and correct treatment should be given. First of all, children with allergic purpura should adhere to long-term follow-up, mainly for regular urine tests. Renal involvement mostly occurs within one month after the onset of the disease and can manifest as mild or severe hematuria, proteinuria, and in some cases, acute/chronic renal failure. Secondly, clinicians should develop an individualized treatment plan according to the symptoms and/or renal pathology. Oral Chinese medicine is sufficient for mild cases, while hormonal and immunosuppressive therapy is required for severe cases. Most children with allergic purpura nephritis have a better prognosis, partly due to the improved understanding of it and advances in diagnosis and treatment in recent years. Adherence to long-term follow-up and regular treatment by the child and his family is very important and determines to some extent the prognosis of the child.