LOCK DEVICE FOR OPENING/CLOSING BODY

Provided is a lock device for an opening/closing body, the device having a reduced number of parts and enabling a key cylinder to be removed with greater ease. The lock device comprises a lock part, a lock member which is operated via a manipulation member, a base member, and a key cylinder, wherein: the manipulation member comprises a cylinder housing part; the base member comprises a cylinder arrangement space in which the cylinder housing part is arranged, a wall part located at the tip side of the manipulation member, and an opening formed in the wall part; the key cylinder comprises a key plate; the key plate comprises a pressing surface; and the pressing surface is exposed inside the cylinder arrangement space and disposed further to the base end part side of the manipulation member than the edge part of the opening in the wall part.