In this paper, we propose a triple-based indexing model for the retrieval of VRML (Virtual Reality Modeling Language) objects. A VRML object is basically a VRML class, which can be presented at WWW through 3D visualization tools. Since a composite VRML object consists of several constituent VRML objects having 3D spatial structure, an indexing mechanism is crucial to fully describe the characteristics of the spatial structure. Triples are used to index the composite VRML object by representing its structure in terms of its constituents and their relative directions. TO enhance recall, the proposed model also provides a mechanism to match two objects, which are equivalent if performing an appropriate rotation transformation. This model is an attempt towards concept-based 3D object retrieval.