||Epoxy resins have been used in a variety of fields owing to its excellent adhesion and insulating properties. However, low thermal conductivity of epoxy resins had limited their application in high-junction and high-density circuit equipment. Recently, researchers have introduced high thermal conducting fillers, such as AlN, SiC, BN, etc., into epoxy resins. In this study, different types of epoxy resins and modified hexagonal boron nitrides (BN) composites were prepared to increase thermal conductivity. The thermal conductivities of 60 vol% BN-epoxy composites improved to 12.93 (BPEP, 3830%), 12.71 (DGEBA, 4761%) and 10.28 W/m∙K (TMBP, 3274%), respectively, compared to pure epoxy resins. As a result, epoxy-BN composites by surface modification could be used enhancement of thermal conductivity.