In this paper, we present the design and implementation of a VRML multi-user layer, which is introduced in the virtual reality platform. A novel 3D simulation system supporting tunnel boring machine (TBM) design is developed. The virtual environment (VE) of the TBM is established by VRML based on virtual reality technology, the 3D assembling model is built by Solidworks software and changed into the virtual environment by VRML format. The optimal method is put forward by three steps optimization data to realize transmission of network. The motion simulation and virtual assembly program for TBM are made by VRML/Java language with the movement simulation control function to realize motion simulation. It has the advantages of free installation, authenticity, interactivity, low-cost, portability, and low requiring for the clients and so on.