Abstract: Corona discharge can adversely affect the stable operation and service life of electrical equipment. Therefore, it is crucial to enhance the corona resistance of insulation materials to ensure the normal functioning of electrical equipment. In this study, modified BN (fBN) was synthesized by treating boron nitride (BN) with a silane coupling agent, and subsequently blended with dispersant (organosilicon boron composite oxide (Si-B)) to modify epoxy resin (EP). The fBN-Si-B/EP composites with different fBN contents were prepared by blending and thermosetting methods. The corona resistance life of epoxy resin was significantly enhanced. The experimental findings revealed that the corona resistance life of fBN-Si-B/EP composites at an electric field strength of 30 kV·mm⁻¹ and temperature of 30℃ was up to 114.8 h, which was 5.01 times greater than that of pure epoxy resin. The dielectric constant of the fBN-Si-B/EP composite shows an increasing trend with the increase of the fBN doping. At the same time, the volume resistivity and breakdown strength of the composites show a trend of decreasing and then increasing. The addition of a small amount of fBN can reduce the relative dielectric constant of the composite and suppress the increase of dielectric loss. While the breakdown strength and volume resistivity of fBN-Si-B/EP composites are slightly reduced with the addition of fBN particles, with a minimum volume resistivity of 6.65×10¹⁴ Ω·cm and a minimum breakdown strength of 24.04 kV·mm⁻¹, they still exhibit good insulation properties.