In this work, we investigated the influence of different concentrations of silver 2-ethylhexanoate on the synthesis and characteristics of silver nanoparticles (AgNPs) in resin matrix, as well as the antibacterial performance, mechanical properties and biocompatibility of the silver containing resin matrix, in order to provide a scientific basis for the application of AgNPs in restoration resins. The concentration of silver salt in resin matrix was set ranging from 0.05 wt% to 0.30 wt%. AgNPs were successfully synthesized in resin matrix by reducing silver ions in situ through photoinitiation. The results demonstrated that silver salt with low concentrations (≤0.20 wt%) had little influence on the degree of conversion, Knoop hardness and cell viability of silver resin matrix. However, silver salt with low concentrations (≤0.15 wt%) had little antibacterial activities against Streptococcus mutans. Therefore, it suggested that 0.20 wt% was a proper concentration for silver salt to be added into resin matrix, since silver salt at this concentration could exert a significantly antimicrobial activity without compromising the mechanical properties and biocompatibility of resin matrix.