Provided is a tube set which is capable of easily determining whether a holder has been mounted when the holder is mounted on a housing. The tube set, which is provided in a tube pump that feeds a liquid, includes a pump tube and a holder. The holder has a flexible flat plate and includes first and second engagement portions located away from each other in a first direction. The first and second engagement portions are configured to be fitted into first and second engagement grooves formed in the housing, respectively, when the holder is pushed into the housing in a state of being bent in a thickness direction. The holder is elastically restored to be attached to the housing when the engagement portions are fitted into the respective engagement grooves. The holder has a flexural modulus of 500 MPa or more and 3500 MPa or less.