Cell culture instrument

A cell culture instrument provided with: a cylindrical first inner tube; a membrane for cell culture, said membrane being disposed so as to wholly cover one end of the first inner tube and folded along the outer periphery of the aforesaid end of the first inner tube toward the outer side surface side of the first inner tube; and an outer tube in a cylindrical shape, said outer tube housing the first inner tube therein in such a manner that the height direction of the outer tube agrees with the height direction of the first inner tube, being provided with a first slit extending in the height direction at least in an area where the outer tube overlaps the aforesaid end of the first inner tube, and holding the membrane for cell culture between the inner wall surface of the outer tube and the outer side surface of the first inner tube. 细胞培养器具具有筒状的第1内筒。另外，具有细胞培养用膜，该细胞培养用膜覆盖第1内筒的个端部整体而配置，且沿第1内筒的所述另个端部的外周而向第1内筒的外侧面侧弯折。另外，具有外筒，该外筒形成为筒状，以高度方向与第1内筒致的方式将第1内筒收容于内部，且至少在与第1内筒的所述另个端部重叠的区域形成沿所述高度方向延伸的第1狭缝，并且在所述外筒的内壁面和所述第1内筒的