The degradation mechanisms with absorption of water boiling are explored for epoxy composite filled with silica particles. The relations between volume fraction of silica particles and dynamic Young's modulus for epoxy composite are measured with the function of square root at boiling time. The silane coupling agents are used for improvent of degradation at interface between epoxy resin and silica partitles with water boiling. The adhesive effects between epoxy resin and silica particles for boiling of epoxy composites are evaluated with the reinforcing model for rubber-particles system.