Components in rocket kerosene were analyzed by gas chromatography-mass spectrometry. In the condition adopted,159 peaks were detected in total ion current chromatogram （TIC） of rocket kerosene,131 peaks among them were identified. The components identified account for 80.37% of total amount of rocket kerosene. It is found in rocket kerosene that,almost half of all components are bicyclo-paraffins,followed by monocyclo-paraffins and iso-alkanes,still by little n-alkanes,oxygen-containing compounds,alkenes,tricyclo-paraffins and aromatics. Most bicyclo-paraffins are alkyldecalins,alkylspiro［5.5］undecanes,and naphthenic cyclohexanes,which respectively account for 49.04%,19.28% and 16.64% of bicyclo-paraffins. Monocyclo-paraffins are mostly alkylcyclohexanes and alkylcyclopentanes,which respectively account for 66.62% and 31.10% of monocyclo-paraffins.