The Ueno Zoo Monorail Line (東京都交通局上野懸垂線, Tōkyō-to Kōtsū-kyoku Ueno Kensui-sen) was a 0.3 km (0.19 mi) long suspended railway operated by the Tokyo Metropolitan Bureau of Transportation (Toei).

The number of cars in Japan rose since the end of World War 2, which caused heavy traffic congestions around Tokyo.

Trams and bus routes operated by Tokyo Metropolitan Bureau of Transportation suffered from delays and loss of passengers caused by traffic congestions.

[8] However, the Bureau of Transportation planned to close the line in 1980 due to financial difficulties and aging of equipments.

[9] On January 23, 2019, the Bureau of Transportation announced that the line will be suspended due to aging of the rolling stocks introduced in 2001.