Abstract: To evaluate the feasibility and accuracy of real-time three-dimensional echocarctio graphic(RT-3DE)planimetry of mitral valve area(MVA)for rheumatic mitral stenosis, MVAs of 42 patients with rh-eumatic mitral stenosis were estimated by two-dimensional echocardiography(2DE),Doppler pressure haft-time (PHT) and volumetric RT3DE. Except one patient with serious calcified mitral valvular conglutination, satisfying RT3DE images of mitral valves were acquired from all other patients.And MVA measured by RT3DE had no significant difference(P>0.05) and correlated well with MVA measured by 2DE and PHT(r₁=0.945,r₂=0.809).RT3DE quantification of MVA for rheumatic mitral stenosis is feasible and accurate.It provides a new quantitative way for clinical MVA evaluation.