To evaluate the accuracy and feasibility of right ventricular function parameters measurement using 320-slice volume cardiac CT. Retrospective analysis of 50 consecutive patients (23 men, 27 women) with suspected pulmonary diseases was performed in electrocardiogram (ECG)-gated cardiac CT and cardiac magnetic resonance (CMR). Parameters including right ventricular end- diastolic volume (RVEDV), right ventricular end- systolic volume (RVESV), right ventricular stroke volume (RVSV), right ventricular cardiac output (RVCO), and right ventricular ejection fraction (RVEF) were semi-automatically and separately calculated from both CT and CMR data. Significant difference between measurements was measured by paired t test and two-variable linear regression analysis with Pearson's correlation coefficient. Bland-Altman analysis was performed in each pair of parameters. There was little variability between the measurements by the two observers (kappa = 0.895-0.980, P < 0.05). There was good correlation between all parameters obtained by CT and CMR (P < 0.001): RVEDV (108.5 +/- 21.9 ml, 113.5 +/- 24.8 ml, r = 0.944), RVESV (69.8 +/- 33.4 ml, 73.2 +/- 35.4 ml, r = 0.972), RVSV (39.0 +/- 13.2 ml, 40.2 +/- 13.3 ml, r = 0.977), RVCO (2.6 +/- 0.7 l, 2.6 +/- 0.7 l. r = 0.958), RVEF (38.8 +/- 19.1 %, 39.1 +/- 19.3 %, r = 0.990), and there was no significant difference between CT and CMR measurements in RVEF (n = 50, t = -0.677, P > 0.05). 320-slice volume cardiac CT is an accurate non-invasive technique to evaluate RV function.