Abstract： Objective To investigate the relationship between body mass index(BMI)and cardiac structure and function of adult men living in Hebei province.Methods A total of 160 adults were assigned to 4 groups by BMI:normal body weight group(group A,BMI 18.5 to 23.9 kg/m2),overweight group (group B,BMI 24.0 to 27.9 kg/m2),mild obese group(group C,BMI 28.0 to 29.9 kg/m2),and severe obese group(group D,BMI ≥ 30 kg/m2).Left ventricular end-diastolic diameter(EDD),end-systolic diameter(ESD),inter ventricular septal thickness(IVS),left ventricular posterior wall thickness (LVPW),left ventricular mass(LVM),and left ventricular mass index(LVMI)were examined by echocardiography.Early(E)peak diastolic and late(A)diastolic mitral inflow velocity and E/A ratio were measured by Doppler echocardiography.Pulsed wave Doppler tissue image(PW-DTI)of the lateral mitral annulus was performed to evaluate early peak diastolic velocity(Em),late peak diastolic velocity(Am)and Em/Am ratio.Results Compared with group A,EDD,ESD,LNM,LVMI,Am,IVS and LVPW were increased in the other 3 groups(all P ＜ 0.05).E,E/A ratio,Em,and Em/Am ratio were decreased in group B,C,and D(all P ＜ 0.05).Compared with group B,Sm was decreased in group C and D(both P ＜ 0.05).Conclusion Overweight and obesity could contribute to ventricular hypertrophy and deteriorate diastolic function in a BMI dependent manner.Obesity may be also related to decreased Sm.