For spacebe multi-beam an-tennas (MBAs), time division multiplexed switching (TDMS) based calibration receiver can reduce implementation costs effectively and is very suitable for large-scale applica-tions. However, in practice, random phase noise imposed by noisy local oscillators can cause significant performance degradation in TDMS-based calibration systems. Charac-terization of phase noise effects is therefore crucial for practical applications. In this paper, we analyze the impact of phase noise on the calibration performance for a MBA system. Specifically, we derive the relationship be-tween the probability of correct amplitude/phase estimation and various practical factors involving the signal-to-noise ratio (SNR), the standard deviation of phase noise, the given tolerance region, and the length of the spread-ing code. The results provide high efficiency for evaluating the calibration performance of the MBAs based on TDMS, especially for pre-cisely anticipating the impact of phase noise. Finally, the accuracy of the derived results is assessed by simulations in different scenarios.