Respiratory gating was proposed to reduce motion blur in cardiac SPECT. This study aims to evaluate 3 respiratory gating methods for cardiac SPECT. We used a population of 4D XCAT phantoms to simulate 10 patients injected with Tc-99mMIBI, 6 with normal heart and 4 with heart defects. Phantoms varied in gender, body size, heart size, activity distribution and breathing pattern. For each phantom, 3 respiratory cycles were divided into 288 frames which were grouped to 6 gates with: (1) equal amplitude gating (AG); (2) amplitude gating with equal counts (CG) and (3) equal time gating (TG). Average activity and attenuation maps in each gate represented gated SPECT and CT. The end-expiratory and end-inspiratory phases were used as references. One hundred and twenty noise-free projections were generated from RAO to LPO using an analytical LEHR projector and reconstructed by OS-EM with 200 updates, using gated CT for attenuation correction. Reconstructed images in each gate were registered to referenced images using affine+bspline method, then averaged and reoriented to generate shortaxis images and polar plots. Relative difference (RD) of the average image intensity was computed at each segment in 17segment analysis based on the references. For all phantoms, the maximum {\mathrm {RD}}-{\mathrm {ALL}} of AG, CG and TG were 7.41 ± 4.45%, 7.10 ± 3.58% and 12.33 ± 3.80% when registered to end-expiration and 6.38 ± 2.68%, 7.22 ± 3.97% and 13.73 ± 4.95% when registered to end-inspiration. We conclude that the amplitude based methods (AG and CG) shows better performance in motion reduction.