To suppress breakage of a branch joint by external force applied in time of connection, and to reduce cost.

The tube cassette includes: tubes 101 having flexibility; and a cassette body 102 harder than the tubes 101, installed with the tubes 101. A port member 104 having a connection port 104a connected to another apparatus by the branch joint 103 is provided in the middle of the long direction of the tubes 101, the cassette body 102 is formed with a through-hole 106, and the port member 104 is supported in the through-hole 106 movably in the connection direction of the other apparatus to the connection port 104a.