A novel membrane was prepd. from poly(acrylonitrile-co-glycidyl methacrylate) (PANGMA) of a defined epoxide content as membrane polymer by a conventional immersion-pptn. phase-inversion process as the first step. Thereafter, both the chem. structure and the morphol. of this membrane could be efficiently stabilized by a post-treatment with ammonia. The result of this ammonolysis reaction is an extensive crosslinking yielding an extraordinary solvent-resistant membrane. Furthermore, that membrane can be safely sterilized by hot steam at 121 or 140 DegC and drying of the membrane on air is possible without any additives. Performance characteristics of PANGMA membranes for aq. solns. are similar to poly(acrylonitrile) (PAN) membranes, but with the novel membrane applications in solvents such as DMF are possible as well. Depending on ammonolysis conditions either residual epoxide groups or primary and secondary amino groups are available on the membrane surface for covalent coupling of ligands.