Abstract: In this article, an analysis of the PRA (plasma renin activity) and ATⅡ (angio- tensin Ⅱ) levels of blood samples from peripheral vein, bilateral renal veins and inferior caval vein and renin related factors in 26 cases of renovascular hype- rtension (RVH) was performed. The conclusions were as follow: (1) The positive rate of renal vein renin ratio (RVRR) was 45.5--53.8% in the unilateral RVH patients. (2) There was no difference in short- term curative effect between the patients with unilateral RVH who have positive and negative diagnostic ratios. (3) The renin activity of blood samples from the renal vein of the affected side can be either high, normal or low. (4) The etiology of some patients with normal and low renin RVH was possibly renal parenchymal involvement, PGE or kinin deficiency. (5) We believe that multiple determina- tions and multiple index observations of RAAS, KKS and PGS can help to clarify the pathogenesis and enhance the positive diagnostic rate of RVH and to pinpoint the indications for surgery.