【Abstract】Objective The purpose of our study was to observe the expression of IL17 in serum and urine of patients with PMN and to explore the possible role of IL17 in PMN.Methods From June 2016 to February 2018, 43 patients with primary membranous nephropathy were selected from the First Affiliated Hospital of Harbin Medical University. According to the pathological stages, the patients were divided into three groups: stage Ⅰ, stage Ⅱ and stage Ⅲ. The general situation, laboratory examination and pathological results of renal biopsy were statistically analyzed. In addition, 43 patients were divided into groups according to whether there was renal tubule and interstitial damage, and the relationship between IL17 and renal tubule and interstitial damage in patients with primary membranous nephropathy was analyzed.Results The level of serum IL17 in stage Ⅱ and stage Ⅲ was higher than that in stage Ⅰ, with statistical difference (P<005). The level of urine IL17 in stage Ⅲ was higher than that in stage Ⅱ, with statistical difference (P<005). The level of serum and urine IL17 in stage Ⅲ was higher than that in stage Ⅰ and stage Ⅱ (P<005). The level of serum and urine IL 17 in patients with different degrees of tubulointerstitial injury was statistically different (P<005).Conclusion IL17 is associated with renal tubular and interstitial injury in patients with primary membranous nephropathy.