This study proposes a multiobjective optimization scheme for synthetic aperture imaging array based on the simulated annealing algorithm (SAA). The spectrum optimization objective of the aperture array is designed in multiple directions based on characteristics of the modulation transfer function (MTF) of synthetic aperture imaging. The degraded Golay6 structure is used as the initial array to perform simulation calculations. The results show that SAA can effectively improve the stability of the MTF in the medium frequency range and considerably increase the actual cut-off frequency of the imaging array. When filling factor F=11.5%, compared with Golay6 aperture array, the average correction factor of the optimized aperture array reaches 8.61% when the annealing attenuation parameter α=0.97.