Abstract: Two series of chiral compounds, esters of ( + )-p-2-methylbutyloxy-phenyl-p-alkyloxy-benzoic acid and esters of ( + )-p-alkyloxy-phenyl-p-2-methylbutyloxy benzoic acid were determinated with electron impact mass spectrometry. The mechanism of their fragmentation was discussed. A commercial chiral liquid crystal mixture is satisfactorily analyzed by using field desorption/mass spectrometry and gas chromatography/mass spectrometry.