In　this　paper,　composites　with　different　contents　of　epoxy　resin/nano-SiO,　were　fabricated,　the　influence　of　compounding　process　on　nano-SiO2　dispersion　was　studied,　the　microstructure　and　the　relationship　between　impact　strength　and　nano-SiO2　content　were　investigated.　The　results　showed　that　the　distribution　of　nano-SiO2　particles　in　the　composites　could　be　improved　efficiently　using　high-speed　shearing　dispersion　method.　To　composites　with　or　without　the　coupling　agent　treatment,　the　impact　strength　grew　with　increasing　nano-SiO2　content,　and　increase　to　a　maximum　value　when　nano-SiO2　content　was　3wt.%.　The　maximum　value　was　75.4%,　and　45.5%　higher　than　that　of　monolithic　epoxy　resin　respectively.　With　the　nano-SiO2　content　increased　continually,　the　impact　strength　of　composite　materials　decreased.　The　coupling　agent　treatment　of　nano-SiO2　administered　to　improve　the　impact　strength　of　the　composites.