Objective：To assess the feasibility and accuracy of real-time three dimensional echocardiography （RT-3DE） in quantitative evaluation of left ventricular （LV） volume and ejection fraction （EF） in patients with ventricular aneurysm and myocardial infarction. Methods： Twenty-three patients with left ventricular aneurysm combined with myocardial infarction were examined by RT-3DE, two dimensional echocardiography Simpson＇s method, and M-mode Teichholz method separately. The following parameters： left ventricular end diastolic volume （LVEDV）, end systolic volume （ESV）, stroke volume （SV） and EF were obtained by each method and the results were compared with those obtained by left ventriculography （LVG）. Results.. The values of LVEDV, LVESV, SV, and EF determined by RT-3DE showed good correlations with those determined by LVG （r= 0.92, 0.90, 0.88, and 0.91, respectively; P〈0. 001）, with the values by RT-3DE slightly smaller than those by LVG（P〉 0.05）. The values of LVEDV, LVESV, SV, and EF determined by Simpson＇s method also showed good correlations with those determined by LVG （r= 0.85, 0.87, 0.86, 0.91, respectively; P〈0. 001） , with the values by Simpson＇s method smaller than those by LVG （P〈0.05 for LVEDV and LVESV）. The values of LVEDV, LVESV, SV, and EF determined by Mmode Teichholz method also showed good correlations with those determined by LVG （r= 0.73, 0. 71, 0.70, 0.65, respectively; P〈0. 05）, with the values by M-mode Teichholz method larger than those by LVG（P〈0.05 or P〈0.01）. Conclusion： RT-3DE is a more accurate for evaluation of LV volume and EF in patients with aneurysm combined with myocardial infarction