In this study, silver nanoparticles (NPs) were considered for the first time as a sintering additive in the manufacture of YAG:Ce luminescent ceramics. The influence of the addition of silver NPs on the sintering kinetics of ceramics was investigated. It was found that the addition of Ag NPs in the concentration range of 0.027–0.44 wt% does not result in the formation of secondary phases in YAG:Ce ceramics. It was demonstrated that the light transmission of ceramics is dependent on the concentration of Ag NPs. The use of NPs additive has made it possible to increase the light transmission of ceramics compared with the reference sample without sintering additives. The combination of two sintering additives, TEOS and silver NPs, enables the achievement of enhanced optical transparency in ceramics compared to the individual application of sintering additives. At an optimal silver concentration of 0.11 wt%, in combination with 0.5 wt% TEOS, a ceramic light transmission value of 77% was attained. The study has identified a correlation between the luminescence intensity of YAG:Ce ceramics and the concentration of silver NPs. It was observed that the utilization of low concentrations of the Ag additive had negligible impact on the luminescence properties, whereas the introduction of high concentrations of Ag NPs led to a deterioration in the luminescence and optical transparency of the ceramic.