Transport of pure propan-1-ol and propan-2-ol through polyethylene membrane during vapor permeation and pervaporation processes was studied at 20degreesC. The permeation experiments for different concentration up to the saturated vapor pressure were carried out. It was verified experimentally that there is not a significant difference between permeation fluxes of saturated vapor of propanols and their pervaporation fluxes. Also, the amount of sorbed propanol from liquid and from saturated vapor is the same. The influence of sorption of permeating molecules on the diffusion coefficient in membrane was investigated. The assumption of two types of permeating molecules in the rubbery polymer (mobile and immobile) was applied for the description of the mass transport through polyethylene membrane. Concentrations of mobile and immobile molecules in the membrane were estimated.