Polymer through-hole membranes were fabricated by nanoimprinting using metal molds with high aspect ratios, which were prepared by a replication process using an anodic porous alumina template. The introduction of a two-layer structure of polymers and the selective removal of underlying polymer layer allows the formation of polymer through-hole membranes. The obtained polymer through-hole membranes will be used for various applications that require highly ordered hole array structures with sufficient chemical stability. (c) 2007 American Vacuum Society.