Abstract: In this study, the position of Faraday Cup of MAT253 mass spectrometer was set according to the motion characteristics of ions in magnetic field after Xe isotope ionization, and the abundance of nine Xe isotopes were measured,in order to accurately measure the Xe isotopic abundance. As a magnetic mass spectrometer, MAT253 has mass discrimination effect when measuring isotope abundance. To address this issue, the internal standard method was used to correct the mass discrimination of Xe isotope abundance values by using power function, exponential function and equilibrium correction law. The relative standard deviation of measurement results was less than or equal to 0.13%, and the Xe isotope abundances obtained by the power fuction correction with ¹³¹Xe/¹³²Xe as internal standard were closer to the natural values. The corrected deviation of each isotope from the reference values were within 1.46%, and the standard uncertainty of each isotope was within 0.21% (k=2).