Objective:To observe clinical effect of addition and subtraction therapy of Zidiantang to purpura nephritis in children （syndrome of blood fever） and regulatory action to immune inflammatory factors. Method:One hundred and twenty-five patients were randomly divided into control group （61 cases） and observation group （64 cases） by random number table. A total of 57 patients in control group completed the therapy （2 patients were falling off or missing visit and 2 was eliminated）， 59 patients in observation group completed the therapy （3 patients were falling off or missing visit and 2 was eliminated）. Both groups' patients got comprehensive measures of western medicine. Patients in control group got Xueniaoan capsule， 1 to 4 grains/time， 3 times/day. Patients in observation groups got addition and subtraction therapy of Zidiantang， 1 dose/day. The treatment was continued for 2 months and the follow up was recorded for a month. Purpura and urinalysis were recorded for every week. And disappearance of purpura， hematuria and proteinuria were compared for 3 months. Before treatment， and at the first， second and during the follow up， scores of 24 h urine protein quantification （24 hup） and syndrome of blood fever were graded. Levels of microalbuminuria （mAlb）， urinary <italic>β</italic>₂-microglobulin （<italic>β</italic>₂-MG）， cystatin C（CysC）， globulin A1（IgA1）， IgG， complement C3， Th17 cells， Treg cells， interleukin-17 （IL-17）， IL-21， IL-10 and transforming growth factor-<italic>β</italic>₁ （TGF-<italic>β</italic>₁） were detected before and after treatment. Result:At the first month of treatment， disappearance rate of purpura in observation group was higher than that in control group （<italic>P</italic><0.05）. Before treatment， and at the first， second and during the follow up， disappearance rate of hematuria and albuminuria were higher than those in control group （<italic>P</italic><0.05）， and scores of 24 h urine protein quantification （24 hup） and syndrome of blood fever were lower than those in control group （<italic>P</italic><0.01）. Levels of mAlb， <italic>β</italic>₂-MG， CysC， IgA1， IgG， Th17， Th17/Treg， IL-17， IL-21 and TGF-<italic>β</italic>₁ were lower than those in control group （<italic>P</italic><0.01）， and levels of C3， CD4⁺， Treg and IL-10 were higher than those in control group （<italic>P</italic><0.01）. Conclusion:On the basis of conventional western medicine treatment， addition and subtraction therapy of Zidiantang can promote the purpura to subside， improve the syndrome symptoms of blood fever， regulate the immune inflammatory reaction， reduce the inflammatory damage of kidney， thus reduce the hematuria and proteinuria， and play a role in protecting the renal function.