The present invention relates to a medical apparatus including a hollow member with inner surface parts configured to be brought into contact with each other through deformation of the hollow member and is directed to provide a medical apparatus wherein inner surface parts of a hollow member are prevented from being adhered to each other. A medical apparatus includes a hollow member (60) whose inner surface parts are configured to be brought into contact with each other through deformation of the hollow member (60) and the hollow member (60) includes a convex and concave portion (70) formed on the inner surface parts configured to be brought into contact with each other.