Left ventricular end diastolic pressure (LVEDP) in 24 patients with coronary heart, hypertension or rheumatic heart disease (mainly aortic valve pathologic change, exclude mitral stenosis), who had unobvious clinical heart failure. Before left heart catheterization pulmonary function were tested by plethysmogram, results revealed: when LVEDP > 15 mmHg in the patients, pulmonary function parameter expectancy value percentage including FEF25-75%, V25, V50, V75, FVC, VC, FEV1.0 were obviously decreased. RV/TLC expectancy value percentage was obviously increased. Pulmonary function parameter expectancy value percentage including FEF25-75%, V25, V50, V75, FEV1.0, FVC, etc. had significant negative correlation with LVEDP (r = -0.715, P < 0.001; r = -0.699, P < 0.001; r = -0.678, P < 0.001; r = -0.671, P < 0.001; r = -0.648, P < 0.001; r = -0.516, P < 0.01; respectively). RV/TLC expectancy value percentage had significant positive correlation with LVEDP (r = 0.515, P < 0.05). The results indicate that testing pulmonary function parameter helps to evaluate left ventricular function and diagnose early (mesenchymal) pulmonary edema.