Objective To evaluate right ventricular(RV) global and regional volume and systolic function by real-time three-dimensional echocardiography (RT-3DE) in normal children with different age.Methods One hundred and ninty-two normal children were divided into five groups by age:group Ⅰ,＜1 years old,32 cases;group Ⅱ,≥1 years old-＜3 years old,46 cases;group Ⅲ,≥3 years old-＜6 years old,36 cases;group Ⅳ,≥6 years old-＜9 years old,41 cases;group Ⅴ,≥9 years old-＜14 years old,37 cases.Full volume imaging of RV was obtained at the parasternal four-chamber view near the apex by RT-3DE.RT-3DE data set were analyzed off-line by TomTec RV-Function.RV were divided into three parts:inflow,body,outflow.The measurements were including RV global and regional end-diastolic volume (EDV),end-systolic volume (ESV),ejection fraction (EF) and the ratio of regional parts EDV to RVEDV. The volume and systolic function were compared in three regional parts.RV global and regional parts EF and the ratio of regional parts EDV to RVEDV were also compared in five age groups.Correlation analysis and curve estimation were studied on RV global and regional EDV with age and physical development indexes.Results In the comparison of three regional parts:inflow EDV and EF were higher than outflow and body parts (P＜0.05).No significant different was found between outflow EDV and body EDV (P＞0.05),however,outflow EF was significant higher than body EF(P＜0.05).The comparison of RV global and regional EF in five age groups were no statistical different (P＞0.12). The ratio of regional parts EDV to RVEDV remained constant in five age groups(P＞0.58).Correlation analysis showed the global and regional RV volume were strongly correlated with age,height,weight and BSA (r＞0.77,P=0.000).The best correlation was found with BSA (r＞0.83,P=0.000).Curve estimation demonstrated that the relationship of RV global and regional EDV with age and physical development indexes could be best expressed by power model,the best matched model were found with BSA.Conclusions Among three regional parts of RV,inflow and outflow parts volume contraction were the two main contribution factors for RV function.In childhood RV volume didn't increase linearly with age and physical development indexes,but in an exponential model.