Renal-type allergic purpura refers to the manifestations of hematuria, proteinuria, and tubular urine due to inflammatory reaction of glomerular capillary collaterals on top of cutaneous purpura, with occasional edema, hypertension, and renal failure. Allergic purpura belongs to systemic small vessel vasculitis, which mainly invades the skin, gastrointestinal tract, joints and kidneys. Renal damage mostly occurs 2~4 weeks after the appearance of purpura, or the appearance can be delayed. Most patients recover completely, while a few cases evolve into chronic nephritis and renal insufficiency due to recurrent episodes. Renal involvement is more common and severe in older children and adults. Patients with renal purpura are advised to go to regular hospitals for timely consultation and standardized treatment under the guidance of doctors.