<p>Polymer materials commonly employed in low Earth orbit (LEO) environments are highly susceptible to atomic oxygen (AO) attack, leading to severe degradation and deterioration of their properties. To address this challenge, 3-glycidyloxypropyltrimethoxysilane-modified hexagonal boron nitride (h-BN@KH560) nanohybrids were synthesized and incorporated into epoxy (EP) composites to enhance their AO erosion resistance. The resulting hexagonal boron nitride-based epoxy nanocomposites (FBN/EP) were systematically evaluated for their tribological performance and AO erosion resistance using a series of characterization techniques. The results demonstrated that the incorporation of h-BN@KH560 nanohybrids significantly improved the wear resistance and AO erosion resistance of the EP matrix. Specifically, the FBN_1.0/EP nanocomposite exhibited an 86.1% reduction in wear rate compared to pure EP, while FBN_5.0/EP nanocomposite achieved optimal AO erosion resistance, with a minimal erosion rate of 3.58 × 10^–24 cm³ atoms⁻¹ at an AO dose of 1.2 × 10²¹ atoms cm⁻². These findings indicate that the incorporating content-induced distribution of h-BN@KH560 within the EP matrix strongly influences the wear resistance of FBN/EP nanocomposites, but there is a relatively minor effect on their AO erosion resistance. The enhanced AO erosion resistance is attributed to the synergistic barrier protection provided by h-BN@KH560 and the formed B₂O₃ and SiO₂ layers under AO irradiation. This study offers a promising strategy for extending the service life of epoxy nanocomposites in harsh LEO environments.</p> Graphical abstract <p></p>