Matrix assisted laser desorption / ionization time of flight (MALDI-TOF) mass spectrometry was used for The mass identification of tetrathiofulvalene compounds. Under The experimental conditions of MALDI-TOF, The samples could be easily desorpted and ionized into single charge ions, The mass spectra with mono isotope resolution could be obtained. The mass analytical results of twenty-four compounds have shown that for The tetrathiofulvalene compounds MALDI-TOF is more effective, more convenient than other mass spectrometry methods.