The Transient Plane Source (TPS) method is one of the most accurate techniques for analyzing the thermal properties of materials, including solids, liquids, and powders. This method enables the evaluation of thermal parameters of anisotropic materials in both radial and axial directions, providing precise and non-destructive measurements for conductive and insulating materials. Temperature control during experiments further improves measurement accuracy. However, a key limitation of this method is the requirement to satisfy specific conditions between the thermal penetration depth and the sensor radius, which can be challenging depending on specimen geometry. In this study, the TPS method was used to determine the thermal conductivity and thermal diffusivity of a graphite composite as an anisotropic material. Despite geometric limitations, the measurement requirements were fulfilled by connecting multiple specimens and eliminating additional thermal contact resistance. Owing to the anisotropic nature of the sample, accurate determination of the specific heat capacity of graphite was also necessary; therefore, a novel measurement approach with an error of less than 7% was proposed. The thermal conductivity of graphite was measured as 20.792 W·m⁻¹·K⁻¹ in the axial direction and 51.390 W·m⁻¹·K⁻¹ in the radial direction. To validate the methodology, aluminum was used as a reference material assuming isotropic behavior. The results confirm that the TPS method is a powerful tool for analyzing the thermal behavior of materials and can contribute to optimizing the design of engineering and energy systems to improve performance and durability.