The pericardial endoscope system (100) includes a sheath (1) and an endoscope (2) inserted into the sheath (1), and the sheath (1) is an annular tip of the sheath body (11). A projection (13) projecting from the surface, and lifting means (14) for lifting the projection (13) from the surface of the heart to a position spaced toward the pericardium in the pericardial cavity, the projection (13) Is provided at a position facing the pericardium side when the protrusion (13) is lifted by the lifting means (14), and a position facing the pressing surface (16) in the radial direction, The distal end surface (2a) of the endoscope (2) includes an opening (15) that can be projected and retracted in the radial direction in accordance with the operation of the endoscope bending portion (21).心嚢内視鏡システム（１００）は、シース（１）およびシース（１）内に挿入される内視鏡（２）とを備え、シース（１）が、シース本体（１１）の円環状の先端面から突出する突起部（１３）と、心膜腔内において突起部（１３）を心臓の表面から心膜側へ離間した位置へ持ち上げる持上手段（１４）とを備え、突起部（１３）は、持上手段（１４）によって突起部（１３）が持ち上げられる際に心膜側に配置される押圧面（１６）と、該押圧面（１６）と半径方向に対向する位置に設けられ、内視鏡湾曲部（２１）の動作に伴って内視鏡（２）の先端面（２ａ）が半径方向に出没可能な開口部（１５）とを備える。
