The influence of roughness on interfacial performances of silica glass/polyarylacetylene resin composites was investigated. In order to obtain different roughness, silica glass surface was abraded by different grits of abrasives and its topography was observed by scanning electron microscopy and atomic force microscopy. At the same time, the failure mechanisms of composites were analyzed by fracture morphologies and the interfacial adhesion was evaluated by shear strength test. The results indicated that shear strength of silica glass/polyarylacetylene resin composites firstly increased and then decreased with the surface roughness of silica glass increased. The best surface roughness range of silica glass was 4060 nm. The main mechanism for the improvement of the interfacial adhesion was physical interlocking at the interface. (C) 2007 Elsevier B.V. All rights reserved.