Molecular transport of aromatic hydrocarbons through nylon/ethylene propylene rubber (EPR) blend has been investigated in the temperature range of 25 to 65 degrees C. The effect of blend ratio on the transport behavior was studied in detail. Nylon/EPR-50/50 blend shows the lowest uptake among all the systems studied. This behavior is related to blend morphology, density, and crystallinity of the blend composition. The transport property was correlated with the extent of interfacial adhesion in the blends. The effects of temperature and penetrant size on the sorption behavior were examined. Thermodynamic and Arrhenius parameters were evaluated from the diffusion data. Theoretical and experimental diffusion results were compared.