PROBLEM TO BE SOLVED: To provide a mass spectroscope capable of carrying out a plurality of measurements simultaneously by mounting a plurality of ion sources on one spectrometer and rapidly switching the ion sources. SOLUTION: The mass spectroscope carrying out mass spectrometry by guiding ion generated at the ion source therein, has a plurality of ion sources, and a deflection means guiding the ion generated leastwise at one ion source out of the plurality of ion sources toward the mass spectrometer. In liquid chromatograph type mass spectrometer, gas chromatograph type mass spectrometer, and plasma ion type mass spectrometer, the mass spectrometry can be carried out while operating the plurality of ion sources. COPYRIGHT: (C)2005,JPO&NCIPI
