Silver nanoparticles (AgNPs) are increasingly used in daily life for their antibacterial properties, but their low stability and high cytotoxicity hamper practical applications. In this work, sodium 1-naphthalenesulfonate-functionalized reduced graphene oxide (NA-rGO) was used as a substrate for AgNPs to produce a AgNP-NA-rGO hybrid. This hybrid showed substantially higher antibacterial activity than polyvinyl pyrrolidone (PVP)-stabilized AgNPs, and the AgNPs on NA-rGO were more stable than the AgNPs on PVP, resulting in long-term antibacterial effects. More importantly, this hybrid showed excellent water solubility and low cytotoxicity, suggesting the great potential application as sprayable reduced graphene oxide based antibacterial solutions.