The modification of the polyester track membranes by treatment in radiofrequency plasma generated by capacitive coupled parallel plate discharge in air and ammonia was studied. The investigation of the surface properties (roughness, pore size distribution, contact angle) before and after the plasma treatments was performed. The treatment resulted in increase of the surface roughness and of the pores effective diameter and change of wettability. Membranes presenting lower or higher contact angles, as compared with the initial one can be obtained by selecting adequate values for the radiofrequency power and treatment time values.