This Item gives the variation of thermal conductivity with temperature for 39 compounds from the normal melting point to 0.9 critical temperature. These compounds include C@ to C@@ alkylbenzenes@ cycloalkylbenzene@ polyphenyl hydrocarbons and fused ring hydrocarbons. The thermal conductivities have been critically evaluated and fitted by a single equation. The coefficients of the equation for each compound are given together with tables of the thermal conductivity at 1OX intervals. The values of critical temperature and normal melting points are also given. An equation for predicting the effect of pressure on thermal conductivity for pressures up to 500 atmospheres is suggested.