The effect of intercalation with CuCl/sub 2/ on the temperature variation of the thermal conductivity, thermopower and electrical resistivity of pitch-derived carbon fibres in the temperature range 2<T<300K is studied. At high temperature, the lattice thermal conductivity is smaller than that of the pristine fibres while at low temperature an enhancement of both the lattice and the electronic thermal conductivities is observed. The thermopower is positive and exhibits a temperature dependence very similar to that generally reported in acceptor-type graphite intercalation compounds.