Thermal degradation behaviors and reaction mechanism of Carbon fibre-epoxy composite, obtained from Chinese widely applied hydrogen storage tank, were studied by thermogravimetry combined with Fourier transform infrared spectrometry at varying heating rates. The pyrolysis of carbon fibre-epoxy composite mainly occurs at 550-750 K. The average value of final residue is 72.42%. The calculated activation energies increase exponentially from 206.27 KJ/mol to 412.98 KJ/mol with the average value of 276.6 KJ/mol. The fourth reaction order model is responsible for the pyrolysis of carbon fibre-epoxy composite. The absorption spectra of the evolved gases provided the information that the main evolved products are H2O, CO2, C=O (acid anhydride, ketone or aldehyde), epsilon- caprolactam, alcohols and phenol. Moreover, C=O group > alcohols > phenol > epsilon-caprolactam > CO2 > H2O. Epoxy is the main pyrolysis crude material in carbon fibre-epoxy composite.