Objective To investigate the relationship between n-terminal pro-brain natriuretic peptide (NT-proBNP) level and echocardiographic parameter in patients with chronic heart failure with preserved ejection fraction (HFPEF) and evaluate the correlation,specificity and sensitivity on these indices.Methods Sixty-six symptomatic patients with isolated diastolic dysfunction and preserved left ventricular ejection fraction (LVEF) (≥ 50％) and forty-three people with normal left ventricular (LV) function were examined by conventional echocardiography,tissue Doppler imaging (TDI).Plasma NT-proBNP levels were determined simultaneously.Results Compared with control group,NT-proBNP,E/Em,LVMI were significantly higher in HFPEF (P ＜ 0.01); NT-proBNP was significantly correlated with E/Em (correlation coefficient r =0.576).Conclusion NT-proBNP,E/Em,LVMI were significant markers for reflecting left ventricular diastolic function and good tools for diagnosing HFPEF.NT-proBNP had a significant negative predictive value (92.7％) when NT-proBNP ＜ 90 pg/ml.