This paper demonstrates the effectiveness of a new antimicrobial suture coating. An amphiphilic polymer, poly[(aminoethyl methacrylate)-co-(butyl methacrylate)] (PAMBM), inspired by antimicrobial peptides, was bactericidal against S. aureus in time-kill experiments. PAMBM was then evaluated in a variety of polymer blends using the Japanese Industrial Standard (JIS) method and showed excellent antimicrobial activity at a low concentration (0.5 wt %). Using a similar antimicrobial coating formula to commercial Vicryl Plus sutures, disk samples of the coating material containing PAMBM effectively killed bacteria (98% reduction at 0.75 wt %). Triclosan, the active ingredient in Vicryl Plus coatings, did not kill the bacteria. Further Kirby-Bauer assays of these disk samples showed an increasing zone of inhibition with increasing concentration of PAMBM. Finally, the PAMBM-containing coating was applied to sutures, and the morphology of the coating surface was characterized by SEM, along with Vicryl and uncoated sutures. The PAMBM-containing sutures killed bacteria more effectively (3 log(10) reduction at 2.4 wt %) than Vicryl Plus sutures (0.5 log(10) reduction).