Provincial Highway 31 (Chinese: 台31線) is a 30.036-kilometre-long (18.664-mile) provincial highway in Taoyuan City, Taiwan. An elevated section of the Taiwan High Speed Rail viaduct and under-tunnel acts as a median for most of the highway, except when the highway is near THSR Taoyuan Station and when the highway is near and on its southern terminus.[2] The highway serves the THSR Taoyuan Station.