To study the role of doppler echocardiography in evaluating cardiac function in patients with pulmonary heart disease. 80 cases of patients with pulmonary heart disease from respiratory medicine inpatient department of our hospital during the period of January 2016 and January 2018 were selected as case group, at the same time, 80 cases of healthy checkup from our physical examination center were selected as control group, all object were given  echocardiography. Twodimensional echocardiography was used to determine left ventricular endsystolic diameter (LVESD), left ventricular enddiastolic diameter (LVEDD), interventricular septal thickness (IVSD), left ventricular posterior wall, thickness(LVPWd), relative wall thickness (RWT), left ventricle myocardium index (LVMI), left ventricular ejection fraction (LVEF), main pulmonary artery diameter (MPAD), right atrial diameter (RAD), right ventricular diameter (RVD),right ventricular fractional area change (RVFAC).Doppler echocardiography was used to determine pulmonary artery systolic pressure (PASP), ricuspid annulus systolicpeak velocity (s’), tricuspid annular plane systolic excursion (TAPSE),  E/E’, E/A, right ventricular myocardial performance index (RVMPI). Results showed that LVESD, LVEDD, IVSD, LVPWd,RWT, LVMI, MPAD, RAD, RVD and PASP of case group were significantly higher than that of the control group, P<0.05. LVEF was lower than the  control group, P<0.05. The indexes of s’, TAPSE, RVFAC in case group were significantly lower than the control group, P<0.05. E/E’ and RV  MPI of case group were significantly higher than the control group, E/A was significantly lower than the control group, P<0.05. Therefore, the role of  echocardiography in evaluating cardiac function in patients with pulmonary heart disease is significant, it has the vital significance in guiding clinical treatment plan formulation.