To calculate the deviations between single station magnitudes and average ones by the statistical methods,the paper selected 499 earthquake events with M_L>1.5 recorded on Jiangxi Digital Seismic Network from October 2007 to December 2015. In terms of the frequency distribution,calibration function,station foundation and azimuth,we analyzed the causes of magnitude deviation. After the correction of the calibration function and the station foundation,the absolute values of magnitude deviation of 68.6 percent samples are within 0.2. And we obtained the corrected values of calibration function and station foundation for the Jiangxi region.