The thermal conductivity of 12 pure organic solvents, acetone, acetonitrile, acrylonitrile, carbon tetrachloride, chloroform, 1,2-dichloroethane, ethanol, ethyl acetate, heptane, tetrahydrofuran, toluene, and water, and eight binary mixtures, acetone + ethanol, acetone + ethyl acetate, ethanol + heptane, ethanol + carbon tetrachloride, ethyl acetate + ethanol, heptane + acetone, heptane + toluene, and water + ethanol, were measured by an absolute transient hot-wire method at some selected temperatures from 253.15 K to 303.15 K. A correlation previously developed was used to calculate the thermal conductivity. The agreement between the experimental and the calculated thermal conductivities is satisfactory.