This study evaluated the performance of gated single photon emission computed tomography (SPECT) with thallium-201 (201Tl) in assessing left ventricular ejection fraction (LVEF), end-diastolic volume (EDV), and end-systolic volume (ESV) in Taiwanese by determining repeatability and correlation with two-dimensional (2D) echocardiography. A total of 18 patients underwent two sequential gated SPECT acquisitions within 30 minutes in the resting state to assess repeatability. Another 28 patients who underwent gated SPECT and 2D echocardiography within 7 days were included for comparison. The two sequential measurements were well correlated with respect to LVEF, EDV, and ESV (r = 0.97, 0.95, and 0.97, respectively, all p < 0.0001). Bland-Altman analysis revealed that two standard deviations of the absolute difference between the two sequential measurements for LVEF, EDV, and ESV were 6.4%, 16.8 mL, and 8.6 mL, respectively. For LVEF, EDV, and ESV, correlations between redistribution 201Tl-gated SPECT and echocardiography were also excellent (all r = 0.83, p < 0.0001). LVEF was similar with 201Tl-gated SPECT and echocardiography, but EDV and ESV were significantly higher with echocardiography (p < 0.05). Our study revealed that 201Tl-gated SPECT has high repeatability and excellent correlation with echocardiography for the assessment of LVEF and volumes in Taiwanese. These results support the clinical application of gated SPECT in routine 201Tl myocardial perfusion imaging in Taiwanese.