Ag-nanoparticle-containing hydrogels were successfully prepared by in situ reduction of silver nitrate in the presence of citrate molecules as stabilizing agent during photoinduced copolymerization of AAm and BAAm. Swelling-de swelling behavior and thermal properties of the synthesized hydrogels were investigated. The interior morphology of the gels exhibit continuity, which is a common feature for hydrogel networks. Antimicrobial activities of the hydrogels were also investigated against pathogenic E. coli O157:H7, S. aureus, and non-pathogenic E. coli K-12, which are model microorganisms for testing bactericidal properties. The hydrogels containing well-dispersed Ag NPs showed significant antibacterial activity.