Abstract: A new method to improve the resolution of quadrupole mass spectrometry is studied theoretically.By adding the dipole combined quadrupole excitation to the main RF,the problem of multiple peaks is improved by ejecting the excess ions near the tilp of the first stable region after splitting into islands.The newly developed stable region is similar to the high stable region,with higher resolution and fast quality separation characteristics.High-precision simulation is beneficial to the study of ion motion characteristics in quadrupole mass spectrometry and it is the key to optimize the performance of quadrupole mass spectrometry.By using MATLAB to simulate ion trajectories,the influence of dipolar combined quadrupole excitation on the change of stable area and the influence of simulation parameters on the transmission,resolution and peak shape were studied.Theoretical simulation shows that the method does not need to modify the mechanical structure,but only needs to modify the control circuit to some extent.