This study investigates the effects of electron beam irradiation on the mechanical and tribological properties of polyetheretherketone (PEEK), with particular focus on modifications resulting from the application of Litol-24 lubricant. Samples of pre-treated PEEK were irradiated at doses of 100, 200, 400, and 600 kGy using the ILU-10 linear accelerator. Comprehensive analyses were conducted, including thermogravimetric analysis (TGA) to assess thermal stability, X-ray diffraction (XRD) to observe structural changes, and the impact of irradiation on microhardness. Tribological performance was evaluated using the ball-on-disc method. Results indicate that irradiation decreases microhardness by approximately 19% and modifies tribological behavior in a dose-dependent manner. TGA results showed subtle shifts in decomposition onset temperatures, with a reduction of about 10°C post-irradiation, while XRD revealed a 12% decrease in crystallinity, affecting mechanical properties. Further investigations demonstrated that lubrication, particularly under high-load conditions, could enhance PEEK’s operational characteristics post-irradiation. The study underscores the critical role of lubricants in improving the wear resistance and durability of PEEK, making it suitable for high-stress applications in mechanical engineering and manufacturing sectors. The analysis highlights the potential of integrating electron irradiation into existing material processing workflows to improve PEEK's properties, thereby extending its utility across various industrial applications. This approach offers a promising avenue for optimizing the performance and longevity of PEEK components, particularly in environments subject to extreme mechanical stresses.