Abstract: Objective: To investigate the relationship of abnormal circadian rhythm blood pressure(BP) ，arterial stiffness index and renal damage in patients with primary hypertension. Methods: One hundred and thirteen patients with primary hypertension were divided into non-scoop shape group (66 cases ) and scoop shape group (47 cases ) . The arterial stiffness index，urinary microalbuminuria, 24 h quantity of urinary protein and renal function of two group were detected. The relationships of abnormal circadian rhythm BP, arterial stiffness index and renal damage in patients with primary hypertension were observed. results: The nocturnal systolic and diastolic blood pressure in non-scoop shape group were significantly higher than those in scoop shape group (P ＜ 0. 01) . The differences of arterial stiffness index，pulse pressure and blood pressure circadian rhythm variations in two groups were statistically significant(P ＜ 0. 01) . The differences of blood urea nitrogen, serum cystatin, serum creatinine and microalbuminuria in two groups were statistically significant(P ＜ 0. 05 to P ＜ 0. 01 ) ，but no statistical significance in the difference of blood uric acid (P ＞ 0. 05 ) . Conclusions: There have relationships between abnormal circadian rhythm BP, arterial stiffness index and renal damage in patients with primary hypertension, it is more significant in non-scoop shape group.