Provided are a highly durable and compact gate valve and a method of installing the gate valve. The gate valve includes a valve cage 12 accommodating a valve body and a sealing band 13 covering between a pair of fluid pipes W and the valve cage 12 under a sealed state. The valve cage 12 includes a pair of protruding tubular portion 12B protruding in a pipe axis direction X from a valve cage body. The sealing band 13 includes a pair of main body portions B1 covering the respective fluid pipes W1, W2 and the protruding tubular portions 12B under a sealed state and a connecting portion B3 connecting the pair of main body portions B1 and formed unitarily therewith and is constituted of a plurality of split members Ba split in a circumferential direction of the fluid pipes W.