This study examined the effect of sulodexide on podocyte injury in rats with adriamycin nephropathy (AN). A total of 36 healthy male SD rats were randomly assigned to three groups: control group, AN group and sulodexide treatment group. Rat models of AN were established by a single tail intravenous injection of adriamycin (6.5 mg/kg) in both AN group and sulodexide treatment group. Sulodexide (10 mg/kg) was administered the rats in the treatment group once daily by garage from the first day of model establishment until the 14th day or the 28th day. Samples of 24-h urine and renal cortex tissues were harvested at day 14, 28 after the model establishment. Excretion of 24-h urinary protein was measured by Coomassie brilliant blue method. The pathological changes in renal tissues were observed by light microscopy and electron microscopy respectively. Heparanase mRNA was detected by RT-PCR. Expressions of desmin, CD2AP and heparanase were determined by immunohistological staining. The results showed that the expressions of heparanase mRNA and protein were increased in the glomeruli of AN rats at day 14 and 28 after the model establishment, which was accompanied by the increased expression of desmin and CD2AP. The mRNA and protein expression of heparanase was decreased in the sulodexide-treated rats as compared with AN rats at day 14 and 28. And, the protein expression of desmin and CD2AP was reduced as with heparanase in the sulodexide- treated rats. Proteinuria and podocyte foot process effacement were alleviated in the AN rats after sulodexide treatment. There was a positive correlation between the expression of heparanase and the expression of desmin and CD2AP (as well as 24-h urinary protein excretion). It was concluded that increased heparanase is involved in podocyte injury. Sulodexide can maintain and restore podocyte morphology by inhibiting the expression of heparanase in AN.