To calculate the deviations between single station magnitudes and average ones by the magnitude of residual statistical methods,the paper selected 13086 seismic events recorded on Inner Mongolia Broadband Digital Seismic Network from January 2008 to November 2015. 6 stations have no deviations and 6 stations have bigger magnitudes caused by site response,weathering and other factors. The station magnitude derivation curve does not change obviously before and after site correction. The average magnitude deviation between these events shows a normal distribution. The magnitude deviation curve along with the epicentral distance is deviating from the zero line. The magnitude deviations of the earthquakes are analyzed on the frequency distribution and quantitative statistics. The China calibration function is suitable for the Inner Mongolia region when the epicentral distance is equal or less than 120km,and the magnitude is higher in other conditions. After site correction of 81 stations,M_L calibration function is modified and the new Inner Mongolia region calibration function is obtained.