We constructed a Large-Scale Low-Noise Wind Tunnel in Maibara to develop countermeasures against aerodynamic noises and investigate aerodynamic phenomena of high-speed trains. It has two excellent features. One is the extremely low background noise that makes it possible to precisely measure the noise generated by the models under test. The other is a large and high-speed moving-belt that enables simulation of the air flow between a train model and the ground under actual conditions. This paper reports major characteristics and performance of the wind tunnel.