Silver nanoparticles (Ag NPs)/graphene hybrid of different Ag NPs content were successfully synthesized by decorating silver on exfoliated graphene layers through a simultaneous thermal reduction of graphene oxide and silver ions. Nitrogen adsorption/desorption analyses and electrical conductivity test were carried out to study the influence of different silver content on the properties of Ag NPs/graphene hybrid. It is found that when the content of Ag NPs is high, the nanoparticles can facilitate the exfoliation of graphene and inhibit its restacking, resulting a larger surface area. And with a different content of Ag NPs, the electrical conductivity was increased by a different percentage (up to 250%). This study provides a fundamental study of the synthesis of Ag NPs/graphene hybrid, which gives a good guidance on tuning the properties of metal/graphene properties.