Lipophilicity was evaluated using reversed-phase thin layer chromatographic procedure on silica gel plate. The retention characteristics of some opiods with similar pharmacophore were determined using a methanol/water binary mixture of varying compositions as mobile phase on OL-C and ODS platforms. In vivo biological parameters were computed with the preADMET software. The degree of agreement in lipophilicity measurements by the two biomembrane models (OL-C and ODS) was determined by the Bland-Altman plot.