To provide a cover for surgical treatment tool capable of suppressing inhibition of contact force measurement.SOLUTION: A cover 10 formed into a cylindrical shape arranged on a surgical treatment tool 50 comprising: a treatment part 53 on an end part of a base part 51 extending in a rod shape； and a joint part 61 capable of operating a posture of the treatment part 53 by remote operation and being provided between the base part 51 and the treatment part 53. The cover comprises: a root part 11 arranged on a part on the base part 51 side and on an outer peripheral surface of the base part 51； a tip part for covering at least a surrounding of a part of the treatment part 53 and on a part on the treatment part 53 side； and a center part 15 which is sandwiched between the root part 11 and the tip part, which covers the surrounding of the joint part 61, and which has high flexibility relative to the root part 11.SELECTED DRAWING: Figure 1【課題】接触力測定の阻害を抑制することができる外科処置具用カバーを提供する。【解決手段】棒状に延びる基部５１の端部に処置部５３が設けられ、基部５１および処置部５３の間に処置部５３の姿勢を遠隔から操作可能な関節部６１を有する外科用処置具５０に配置される筒状に形成されたカバー１０であって、基部５１側の部分であって基部５１の外周面に配置される根元部１１と、処置部５３側の部分であって処置部５３の少なくとも一部の周囲を覆う先端部と、根元部１１および先端部に挟まれた部分であって関節部６１の周囲を覆うものであって、根元部１１と比較して柔軟性が高い中央部１５と、が設けられていることを特徴とする。【選択図】図１
