PROBLEM TO BE SOLVED: To provide a transfusion tube set capable of being attached always in an appropriate state even when detailed confirmation of a transfusion tube is not performed in attaching the transfusion tube set to a transfusion device.SOLUTION: A transfusion tube set to be attached to a medical transfusion pump or transfusion device with positioning comprises: a drip tube 5 connected to one end of the transfusion tube set a needle with wing 8 connected to the other end through a tube connection tool 7 and an upper positioning member 2 and a cassette member 3, which is a lower positioning member, positioned close to the middle of the transfusion tube set. A transfusion tube 1s section between the drip tube and the tube connection tool is made of a tube without a joint. The cassette member is composed of a cassette body and a cassette clamp that engages with or fits to the cassette body and moves in an oblique direction. Locking act and unlocking act of a lock lever provided at the transfusion pump or a door of the transfusion device makes the cassette clamp move in an oblique direction, which can open and close the transfusion tube.
