Several carbon fibres issued from different precursors (PAN, PITCH, methane) treated or not treated at high temperature (HTT) were characterized by different physical (XR diffraction, mechanical and electrical properties measurements) and electrochemical methods in order to ascertain the fibres for which intercalation of chemical compounds could give electrical conductivities as high as those metallic conductors. The better ones are the vapour grown fibres (HTT 2 900°C) and some ex-PITCH fibres (P 55, HTT 3 300°C). Ex-PAN fibres do not possess the qualities required to give for intercalation compounds with a good electrical conductivity Caracterisation de fibres obtenues a partir de polyacrylonitrile de brai ou de methane, traitees ou non a haute temperature, par diffraction de rayons X, resistance a la traction et module d'Young, conductivite electrique et insertion electrochimique de H 2 SO 4