Objective To investigate the correlation between benign prostatic hyperplasia (BPH) and blood pressure variability (BPV) in the elderly patients with H type hypertension.Methods 561 elderly patients with H type hypertension from 2010 to 2012 were enrolled in this study,including 436 BPH patients and 125 non-BPH (NBPH) patients.All patients underwent ambulatory blood pressure monitoring (ABPM) and ultrasound examination of prostate.The 24-hour systolic blood pressure variation (24 h SBPV),24 hour diastolic blood pressure variation (24 h DBPV),daytime systolic blood pressure variation (dSBPV),daytime diastolic blood pressure variation (dDBPV),nocturnal systolic and diastolic blood pressure variations were recorded and compared.The differences in blood pressure variation between the two groups were compared.Correlation between BPV and prostatic volume (PV) was analyzed.Results There were no statistical differences in variabilities of 24 h SBPV,nSBPV and dSBPV between BPH group and NBPH group(all P＞0.05).24 h DBPV,nDBPV and dDBPV were significantly higher in BPH group than inNBPH group [(18.5±3.3) mmHg vs.(14.1±3.7) mmHg,(17.1±3.4) mmHg vs.(14.9 ±3.4) mmHg,(16.6±4.1) mmHg vs.(12.8±5.1) mmHg,respectively,all P＜0.05].There were correlations of 24 h DBPV,nDBPV and dDBPV with PV (r =0.137,0.032,0.079,respectively,all P＜0.05).Conclusions The diastolic blood pressure variability may associate with the degree of prostatic hyperplasia in the elderly patients with H type hypertension.