For pancreatic islet transplantation, many kinds of polymeric and silicon based immunoisolation filters have been introduced to circumvent immune rejection,. However, these couldn’t show sufficient feasiblility on porosity, accurate cut-off range and bio-fouling effect by immne molecules. In this study, 14.6 nm pore anodic aluminum oxide (AAO) membrane was fabricated using covalently bonded poly-ethylene oxide (PEO), which was verified that the chosen pore diameter had selectivity to block the smallest immune molecule, immunoglobulin G (IgG), having sufficient porosity for glucose, insulin and oxygen to pass through. Also, to check antifouling, IgG adhesion was checked on PEO coated membrane and poly-ethylene glycol coated capsule and tubing components. Encapsulation system was developed using the membranes, sufficiently mantained survival and functionality of transplanted islets We expect that the AAO membrane will contribute immunoisolation in xenogeneic transplantations.