Due to the influence of environment and multipath effect, the calibration data of spherical near-field antenna measurement are not accurate, which will result in amplitude and phase errors in the near-field to far-field transformation. In order to obtain more accurate antenna radiation pattern, the influence of amplitude and phase errors on the near-field to far-field transformation results are simulated. According to the analysis results, the amplitude and phase errors can be controlled within the tolerable range when the system is designed.