Influence of array errors of azimuth multiple-phase-center (AMPC) synthetic aperture radar (SAR) on signal reconstruction performance is investigated. The array errors were modeled as stochastic process. In combination with least-square (LS) algorithm, the analytical expression of the reconstruction error power spectrum was derived. Then, the analytical expressions of signal to noise ratio (SNR) and azimuth ambiguity to signal ratio (AASR) were obtained. Experiment results confirm the validity of the theoretical analyses. Analytical results indicate that the image quality of AMPC SAR can be improved by decreasing the reconstruction coefficient when the pulse repetition frequency (PRF) increases. The approaches and results are helpful to the system design and the image quality evaluation of AMPC SAR. 