Polymer dielectrics are the most popular materials that have been used in energy storage applications. This returns to its high dielectric strength as well as energy storage capabilities. Recently, polymer composites have been developed for this purpose. One of the promising fillers that can be added for this application is graphene particles due to its high energy storage capacity. Thus, this study aims to increase the energy storage capacity of epoxy resin by incorporating different loading of graphene particles. The prepared samples of graphene-epoxy composites were fabricated with 0.1%, 0.2%, and 0.3% weight percentages of graphene content. Thermal Gravimetric Analysis (TGA) was used to study the thermal stability of the prepared samples of graphene-epoxy composites. On the other hand, the relative permittivity and the dissipation factor for each prepared sample were evaluated by measuring its resistance and capacitance using LCR meter with equivalent parallel model. The obtained measurements indicated that the thermal stability and the dielectric properties of the selected epoxy resin were successfully improved by incorporating of graphene particles within the polymer chains of the epoxy resin. The best filler loading of graphene-epoxy composites was identified considering the thermal stability and the dielectric properties.