Objective To investigate the curative effect of low molecular heparin calcium on Henoch-Schoenlein purpura(HSP) and the preventive effect on Henoch-schonlein purpura nephritis.Methods One hundred and three patients with HSP were enrolled in the study and divided randomly into two groups,heparin group(57 cases) and control group(46 cases).Heparin group received low molecular heparin calcisymptom remission time,the incidence of recurrent skin rash were recorded.The contents of D-dipolymer and the three indicators of early renal damage were detected before and after the treatment.Results The remission times of purpura,joint pain and abdominal pain in heparin group[(15.23±3.14) d,(6.80±1.96) d and(6.68±3.42) d]were significantly shorter than those of control group[(17.11±4.79) d,(8.30±2.67)d,(8.59±4.09) d](P ＜0.05).The incidence of recurrent skin rash in heparin group(14.6%) was significantly lower than that of control group(39.1%)(P＜0.01).Compared to control group,the positive rate of D-dipolymer in heparin group was higher(15.8% vs 37.0%),and the urine levels of mALB,β2-MG and NAG were significantly decreased[(12.22±3.92) mg/L,(5.35±0.51) mg/L,(8.12±.65) U/L vs (14.15±5.17) mg/L,(6.54±2.67) mg/L,(10.04±2.60) U/L]during 3 months after treatment(P＜0.01,P ＜0.05).Conclusion Low molecular heparin can shorten the course of HSP and prevent the development of Henoch-Schonlein purpura nephritis.