VRML is the standard language to build a Virtual Reality System, i.e. a language to describe 3D objects and interactive worlds. To use such a system, among the other tools, a software called browser is needed, in order to access the information in the VRML files and to visualize the virtual world from a human perspective. This paper describes the implementation of a VRML parallel browser based on a modified version of graphics libraries, such as OpenGL and GLUT. The obtained interactive parallel rendering engine has been developed for a message passing computing environment; a detailed analysis of its performance on a PC cluster is also described.