Silicone rubber particles with different degrees of crosslinking were prepared. Silicone oils containing Si-H groups and vinyl groups were reacted at various mol ratios in their composite emulsions. Epoxy resin was modified using these particles and the results indicated that the content of the silicone rubber particles, the crosslinking degree of the rubber particles, and the addition of a coupling agent affected the properties of the modified epoxy resins. The influence of the coupling agent depends on the crosslinking degree of the silicone rubber particles.