Abstract: Gas chromatography-mass spectrometry (GC-MS) is one of powerful instrument analysis techniques,which combines high separation power of GC with precise compound identification of MS. Nowadays,GC-MS has showed many important applications in varies industrial fields,like petrochemical industry,environmental monitoring，food safety analysis,pharmaceutical analysis and national defense industry,etc. In this paper,the applications of GC-MS in forensic science were reviewed,including the determination of the writing time of documents,the investigation of the cause of fire and other general physical evidence identification,drug abuse analysis,explosive residue analysis,etc.,in order to provide useful reference for court analysis practice.