Objective: To investigate the relationship between ambulatory arterial stiffness index (AASI) and left ventricular mass index (LVMI) in the elderly hypertensive patients. Methods: This study population consisted of 332 elderly hypertensive patients, who hospitalized in our department from January 2012 to December 2014.AASI was calculated from 24 h ambulatory BP monitoring recordings and LVMI from echocardiography examination.According to the median value of AASI, patients were divided to less than the AASI median group (low AASI group) and equal to or above the AASI median group (high AASI group). Differences between two groups were evaluated using the Student's t-test and Chi-square test.Univariate association was assessed by the Pearson correlation analyses.Multivariate linear regression models were performed to analyze the correlation between AASI and LVMI. Results: LVMI was significantly higher in high AASI group compared with low AASI group ( (115.91±21.36) g/m2 vs.(104.11±17.24) g/m2,P=0.008). Pearson correlation analyses showed that AASI and 24 h pulse pressure were positively correlated to LVMI (r=0.332, P<0.001; r=0.169, P=0.002). In multivariate linear regression model, AASI(β=44.48, P<0.001), LDL-C(β=-5.97, P<0.001) and UA (β=0.02, P=0.045)showed significant association with LVMI. Conclusion: AASI independently associated with LVMI, and AASI might be one predictor of left ventricular hypertrophy in hospitalized elderly hypertensive patients.