The endoscope cap includes a cap body, a mounting portion, a pressing region in a circumferential direction of the cap body at a distal end portion of the cap body, and a pair of elastically deforming portions that are elastically deformed due to the application of an external force to the pressing region And a non-pressing region located on the opposite side of the pressing region with the pair of first deforming parts interposed therebetween, wherein the pressing region has higher rigidity than the non-pressing region, and the cap The main body is elastically deformed such that the pair of first deformable portions are spaced outward in the radial direction of the cap body as the external force is applied to the pressing region, and the pressing region and the non-pressing region Are elastically deformed such that the opening area of the distal end of the cap main body becomes narrow.本内視鏡用キャップは、キャップ本体と、装着部と、前記キャップ本体の先端部における前記キャップ本体の周方向に、押圧領域と、押圧領域に外力が加わることに起因して弾性変形する一対の第一変形部と、前記一対の第一変形部を挟んで前記押圧領域の反対側に位置する非押圧領域と、を備え、押圧領域は、前記非押圧領域よりも剛性が高く、前記キャップ本体は、前記押圧領域に対して前記外力が加わることに伴い、前記一対の第一変形部が前記キャップ本体の径方向外側に離間するように弾性変形し、前記押圧領域と前記非押圧領域とが近接して前記キャップ本体の前記先端の開口面積が狭くなるように弾性変形する。
