This thesis deals with a 3-Dimensional (3D) Virtual Reality environment simulation, two military training environments were simulated. The simulation consists of two soldiers controlled by the user (user soldiers) and nine enemy soldiers for each environment. In non-network mode of the simulation, the user can control any one of the user soldiers manually at anytime, and give orders to the other user soldier that is controlled by the computer. Each enemy soldier guards a specific point in each environment and is controlled by the computer. Enemy soldiers are alarmed when they see user soldier dead or alive, or when they see another enemy soldier alarmed (running) or dead. For each environment, there are two versions of the software, the client and the server. The client can be operated from another computer that has a network connection with the computer that is operating the server version of the software. The user from the client computer can see all the events that are happening in the server side from a totally different perspective than that of the server side (network mode 0). Also, the client can choose a user soldier and participate in the action (network mode 1). Two network modes were designed: one for monitoring only, and the other for participating in action. The user can use the mouse as an input device for shooting enemies and the standard keyboard, while Wii Remote or GPS can be used to move the soldier in the environment. The project consists of several systems that are designed separately and used by processes to achieve different tasks. The 3D objects were designed using programs like 3D Studio Max 9 and Milkshape 3D 1.8.2. The soldiers were animated in the program Character FX 1.3.4. The programming was done using the Microsoft C# 2008 programming language and the Microsoft XNA 3.0 graphics library. The system was tested heavily and the results were satisfactory.