Low-temperature air plasma was used to treat the cellulose membranes by varying the period of time from 10 to 30 minutes. The surfaces of membranes were changed from hydrophobic to hydrophilic membranes. The contact angles of treated membranes were increased when increasing time to treat. The surface modifications of membrane before and after treated were characterized by SEM. It is shown that air plasma treatment is used to improve the roughness. The dielectric property was also studied.