Provided is an in-vivo indwelling tube having a high flap strength and capable of smoothing the passing through a conduit of an endoscope. A method for producing an in-vivo indwelling tube having one end and the other end, the method including the steps of: arranging, in a lumen of the first tubular member, the other end of the second tubular member； joining the first tubular member and the second tubular member； arranging the second tubular member in a lumen of a third tubular member in which an axial length is shorter than the second tubular member； joining the second tubular member and the third tubular member； arranging one end of the second tubular member in a lumen on the other end side of the fourth tubular member including a flap with a base end and a free end； and joining the second tubular member and the fourth tubular member.
