Background: Reflection pressure may influence the clinical course of chronic kidney diseases (CKDs). The relationship between the augmentation index (AI) and progression of non-diabetic CKDs was characterized. Methods: Ninety-nine patients were enrolled into the study. Pulse wave form analysis was performed to determine AI that assesses arterial stiffness. Results: In a cross-sectional study, a multiple regression analysis found that AI correlated positively to age and weight, and negatively to height and heart rate (R<sup>2</sup> = 0.50). Furthermore, echocardiography was performed in 51 patients who gave their consent. In male patients under angiotensin inhibition, left ventricular mass index increased as AI was elevated (r = 0.33, slope = 0.85 ± 0.30 g/m<sup>2</sup>/%, p < 0.05, n = 23). A prospective study was performed in 41 patients who consented to having their creatinine clearance measured repeatedly. In the patients with angiotensin inhibition a higher basal AI resulted in a greater annual decrease in creatinine clearance (r = –0.52, slope = –0.43 ± 0.14 ml/min/year/%, p < 0.01, n = 27). Conclusion: The present data indicate that AI as well as angiotensin contribute to the development of left ventricular hypertrophy. Furthermore, our results suggest that in addition to angiotensin, AI is a risk factor of progression of non-diabetic CKDs.