This study is aimed at investigating the microbiocidal potential of amino-functionalized poly(norbornenes) in the solid state. A series of norbornene-type monomers that carry secondary or tertiary amine functions as well as hexyl and dodecyl groups were prepared. Ring-opening metathesis polymerization was used to prepare homopolymers of the amine bearing monomers and random copolymers of amine-and alkyl-substituted monomers of high average molar mass. The resulting polymers were characterized by nuclear magnetic resonance, thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and contact angle measurements, and their contact biocidal potential was evaluated according to the Japanese Industry standard Z2801. Tested microorganisms comprised Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger. Microbiocidal activity of selected polymer films against E. coli, S. aureus, and A. niger was found, whereas against C. albicans and P. aeruginosa microbiostatic behavior was observed. Moreover, the most potent copolymer revealed no cytotoxicity rendering a biocidal polymer with potential applications in mammalian-, and in particular, human-related fields. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4504-4514, 2010