The endoscope system is arranged on an insertion portion extending in a predetermined axial direction, a tip member arranged at the tip portion of the insertion portion, and a ring-shaped insulation arranged on the proximal end side of the tip member and along the axis. An endoscope provided with a portion, an opening attached to the tip portion to expose a part of the tip member, and an inner portion arranged on the proximal end side of the opening and in close contact with the outer peripheral surface of the insulating portion. A tip cover provided with a peripheral surface thereof is provided, and the outer peripheral surface of the insulating portion and the inner peripheral surface of the tip cover in close contact with the insulating portion are formed by a curved surface over the entire circumference around the axis.内視鏡システムは、所定の軸方向に延びる挿入部、前記挿入部の先端部に配置された先端部材、および前記先端部材の基端側に配置され、前記軸周りに沿ったリング状の絶縁部、を備えた内視鏡と、前記先端部に装着され、前記先端部材の一部を露呈させる開口、および前記開口よりも基端側に配置され、前記絶縁部の外周面に密着する内周面、を備えた先端カバーと、を具備しており、前記絶縁部の外周面とこれに密着する先端カバーの内周面とは、前記軸周りに全周に亘り曲面で構成される。
