Abstract: This work introduces a novel electron source linear ion trap/time-of-flight hybrid tandem mass spectrometer. The system combine advantages of linear ion trap (LIT) and time-of-flight (TOF) mass spectrometry and it feathers good qualitative abilities. Standard sample of PFTBA, carbon tetrachloride and acetone is used to test the performances. The basic functions including ion trapping, isolation, collision induced dissociation (CID) and LIT-TOF interface has been proved to be excellent. Ion isolation and CID experiment of PFTBA fragment ion are demonstrated. Precise isotope ions isolation experiments shows the good selectivity performance of LIT. The EI LIT-TOF established in our laboratory can be applied to the fields of study the structure and chemical characters of volatile organic compounds (VOCs).