ABSTRACT Graphene (GA), a two-dimensional nanomaterial, is noted for its exceptional mechanical, thermal and electrical properties. The integration of GA with road materials can potentially develop high-performance composite road materials. However, its application in road engineering is limited by complex preparation processes and high costs. This paper presents a GA/h-BN composite material developed through mechanical stripping using flake graphite and hexagonal boron nitride (h-BN). A mathematical model was created employing uniform design methods and optimised through numerical analysis to identify the optimal process parameters. Microscopic techniques, including X-ray diffraction and atomic force microscopy, confirmed that the GA/h-BN product consists of approximately three layers, forming a ‘graphene-hexagonal boron nitride-graphene’ nanolayer structure. The composite was then used to modify matrix asphalt, with performance tests determining the optimal dosage. The results indicated that adding 0.3% GA/h-BN significantly improved the asphalt's high- and low-temperature performance, fatigue resistance and cracking resistance. Moreover, the evaluation of the physical properties of matrix asphalt modified solely with h-BN revealed that, despite h-BN comprising 70% of the mass fraction in the GA/h-BN modifier, it exerted a minimal impact on the performance of the asphalt. This study introduces a novel source of raw materials for the application of GA in road engineering.