The soluble deposits on deactived catalyst of cyclohexanone ammoximation system were analyzed by gas chromatography-mass spectrometry (GC-MS). Sample for analyzing was prepared by HF dissolution and ether extraction method. The GC conditions were as follows:an HP-5quartz capillary column (30m× 0.25mm×0.25μm), flowrate of carrier gas helium 0.8mL/min; oven temperature program started at 40℃, then increased to 240℃ at a rate of 20℃/min, finally held at this temperature for 5min; inlet temperature 250℃, sample volume 0.2μL. The MS conditions were that electron impact energy of mass spectrometer 70eV, mass range 10~450m/z, detector temperature 280℃. The result shows that the main soluble deposits on deactived TS-1are products of cyclohexanone oxidation/ reduction, dimers of cyclohexanone, continuous reaction products of cyclohexanone oxime, tert-butylcyclohexanone and a small quantity of other organic compounds. The testing conclusion might be useful in solvent selection and mechanism investigation of deposits formation on TS-1.