The experimental Rm values for a series of aminoalkanethiosulfuric acids, mercaptoalkanamines and aminoalkyl disulfides were determined by reverse phase thin layer chromatography. The Rm values were determined for various concentrations of methanol: water and the correlation obtained was extrapolated to 100% water. These values permitted the calculation of the log P values for each substance. The log P values obtained by this method were compared with those obtained using the shake-flask method and by theoretical calculations utilizing fragment constants.