Abstract: Bamboo fiber/vinyl ester resin (BF/VE) composites were prepared via vacuum-assisted resin transfer molding (VARTM). Nano-SiO₂ modified by coupling agent KH602 was used to modify BF and VE resin, the surface physical and chemical properties of modified fibers and resin were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). Analysis of SEM and FTIR results show that nano-SiO₂ is successfully grafted onto the BF surface and dispersed into the resin matrix; Nano-SiO₂ is more evenly dispersed in BF1/VE0.5 (1.0wt% modified nano-SiO₂ was used to modify BF and 0.5wt% modified nano-SiO₂ was used to modify resin) composites. The mechanical properties, fracture and surface morphologies of BV/VE composites were analyzed by mechanical testing machine and SEM. Effects of the modified nano-SiO₂ addition content on the mechanical properties and interfacial properties of BF/VE composites were investigated and analyzed. Through mechanical tests, the tensile, flexural and impact strengths of the BF1/VE0.5 composites reach to the maximum value of 49.0 MPa, 70.6 MPa, and 150.4 J/m, which are increased by 18.9%, 26.1% and 70.7% respectively compared with the untreated composites. Besides, the interface enhancement mechanism of modified nano-SiO₂ was preliminarily discussed.