A catheter set includes a catheter and a fixing device. The fixing device includes a tubular member which is formed in such a way as to increase or decrease in diameter under axial extension or compression. A first projection and a second projection are provided at both ends of the tubular member. A movable tubular body is disposed around the tubular member between the first projection and the second projection. A distal part is coupled to the tubular member by a support member. The distal part is disposed distally of the tubular member and is configured to at least contact a proximal portion of a tubular device for medical use through which the catheter runs.
