The work aims to prepare graphene/Nano Ag composite with excellent conductivity and improve the conductivity of conductive ink as conductive filler. The method of Hummers was applied to prepare graphene oxide. With glucose as a reducing agent, the graphene /Nano Ag was prepared by synchronous reduction method. The graphene/Nano Ag composite and Nano Ag were mixed as conductive filler to prepare conductive ink in different proportions. By using TEM, XRD, FTIR spectrum and other testing technology, the micro-structure and morphology of the graphene/Nano Ag composite were characterized. The four probe method was used to detect the conductivity of the ink. The results showed that Nano silver particles uniformly dispersed on the graphene surface, and the size of Nano Ag particles was about 35 nm. When the mass fraction of graphene/Nano Ag composites was 12%, the resistivity of conductive ink could reach 1.08×10−7 Ω•m, and the electrical conductivity could be increased by about 64%. The prepared composite graphene is flaky, and its structure is perfect. It can obviously improve the conductivity of conductive ink after added into the conductive ink.