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Aiming at the gas generation characteristics of coal measures source rock during the high evolution stage, which cannot be investigated by the common pyrolysis equipment, the TG-MS (thermogravimetry-mass spectrometry) equipment was employed to study the pyrolysis products characteristics of coal, and then hydrocarbon gases generation kinetic behaviors were investigated. The results show that the mass loss of coal can reach 40%, and can be divided into three stages; moisture and adsorbed gas loss, macromolecule bond cracking loss and the poly-condensation of the aromatic structure loss. Methane starts to generate at about 300 °C, and its generating rate reaches the highest value when the temperature reaches 480 °C. The termination temperature of methane is about 850 °C, which is higher than that of other hydrocarbon gases. The aromatic and aliphatic products are controlled by chemical reactions with the same functional groups, and the benzene evolution curve shows double peaks. Kinetic model parameters of hydrocarbon gases from coal degradation and the geological application results show that the generation activation energy increases with the decrease of gas molecular weight, and the lower molecular weight of hydrocarbon gas, the later of the generation time. The hydrocarbon gas generation history also shows that the gas generation time is long and no major generation period. [ABSTRACT FROM AUTHOR]