We have developed a VR skiing system to train skiing amusingly and effectively. The system consists of a skiing training machine, 90 inch screen, a projector and 3 PCs. A skier rides on the skiing training machine which is fitted with 9 weigh/angle sensors, and enjoys skiing on a "virtual slope". Using measured data by these sensors, developed system simulates the skier's motion on the virtual slope. The simulation is based on dynamics model of real skiing. Acoording to the simulated skier's motion, CG images and sounds of the virtual slope are generated. Therefore he can experience realistic skiing. In addition, some skiers can ski on same virtual slope at the same time and enjoy a dual slalom, because the systems can connected to each other through network.