Abstract: With its high sensitivity and selectivity, mass spectrometry has become an essential tool for analyzing fatty acids. Due to the low ionization efficiency of fatty acids, direct detection by mass spectrometry has low sensitivity and often requires the derivatization treatment. The common mass spectrometry platforms, including gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), capillary electrophoresis-mass spectrometry (CE-MS), and mass spectrometry imaging (MSI), were reviewed. Derivatization methods and optimal reaction conditions commonly used according to different mass spectrometry analysis methods were summarized. The future development direction of mass spectrometry analysis of fatty acids was prospected to provide reference and guidance for related research in forensic science（62 ref. cited）.