Abstract: The quadrupole mass spectrometers are used for analyzing residual gas and measuring the flux under the vacuum as one of the partial measurement apparatus,so it’s metrological characteristics need to study further.This paper use three kinds pure gas N₂、Ar、He to take experiments,And in order to analyse each apparatus metrological characteristics by studying linearity,stability,short term stability,the parameter of ion source and the using history,which apply widely and have some typical character.The conclusions have some vital references on applying the quadrupole mass spectrometers.