PEEK surface copper metallization is widely used in fields such as power, electronics, and new energy. To enhance the mechanical and electrical characteristics of copper coating on PEEK surface further, this study employed a cold spraying deposition technology of graphene-reinforced copper composite coatings. The investigation focused on the properties comparison between composite coatings and pure copper coatings, and systematically studied the influence of nozzle speed within the range of 50–200 mm/s on the structure and properties of composite coatings. Results show that the mechanical and electrical properties of composite coatings are far superior to those of pure copper coatings. And results indicate that at a nozzle speed of 100 mm/s, the composite coating exhibits the densest structure, with a porosity of 0.31% and minimal graphene aggregation, resulting in superior mechanical and electrical properties. Specifically, the friction coefficient is reduced by 46.81% compared to pure copper coating, measuring 0.4046. Additionally, the Vickers hardness of the composite coating reaches 105.96 HV, and its wear rate is 70.59% lower than that of pure copper coating, at 4.32·10−4 mm3/N·m. Furthermore, the conductivity peaks at 1.295·105 S/cm, representing a 38.77%, increase over pure copper coating.