This study used an electric discharge machine (EDM) to perform the electrical spark discharge method (ESDM) to prepare a graphene colloid and a graphene-Ag colloid. The characteristic wavelengths of graphene, and graphene-Ag are both 262 nm. They had the properties of high dispersion and are unlikely to aggregate. The XRD patterns of graphene and graphene-Ag are typical carbon diffraction peak angles and crystal orientations. Graphene-Ag in DW can increase the Raman signal intensity of graphene. Regarding the graphene colloid and graphene-Ag colloid, their average sheet resistance values are 0.0329 MΩ/sq and 0.00136 MΩ/sq, respectively. Moreover, when AgNPs composited with graphene layers, the average sheet resistance is only 1/24 that of graphene layers, indicating that graphene-Ag has superior conductivity.