The results of a study of C-1-C-4 alkane gas permeability and C-5-C-6 alkane and methanol vapor permeability through pressed foil based on exfoliated graphite with a density of 1 g/cm(3) are presented. It has been found that the permeability of the studied graphite foil to C-4-C-6 hydrocarbons is higher than calculated values; in particular, reverse selectivity for pairs such as H-2/hydrocarbon and N-2/hydrocarbon is observed. This can be due to a considerable effect of a surface flow on the total flow through the membrane.