Three years have passed since RTRI's Large-Scale Low-Noise Wind Tunnel was completed at Maibara in 1996. This wind tunnel was built to study aeroacoustic and aerodynamic phenomena for high speed trains and to develop measures for reducing them. This has two excellent features: one is the extremely low background noise and the other is a large and high-speed moving ground plane which enables to simulate the flow between the model and the ground. Here the trend of the utilization of this wind tunnel for three years, an outline of wind tunnel tests and prospects for the future are reported.