Graphene has been investigated as a transparent conductive film for use in a variety of devices, and in recent years it has shown promise for use in millimeter-wave devices as 5G technology. In this study, we applied single-layer (SL), triple-layer (3L), and p-type doped 3L graphene to coplanar waveguide (CPW) transmission lines of practical sizes and obtained transmission characteristics from 1 to 50 GHz, which covered the 5G band. Furthermore, an equivalent circuit model of the CPW used in the measurements was constructed, and simulations were performed, which showed good agreement with the measured results. The results validated the transmission properties of the graphene and the contact impedance with electrodes and the graphene in CPW circuits. In addition, by comparing the transmission loss of various types of graphene, the parameters for improving the transmission characteristics were clarified.