To provide a method for producing a tapered hollow tube which reduces warpage caused by the dislocation of the fiber orientation angle of a prepreg caused by the shape of the taper.

In the method for producing the tapered hollow tube, a trapezoid has a side arm 10 perpendicular to an upper bottom 12 and a lower bottom 14. Four prepregs having approximately the same shape in which the axial direction of reinforcing fibers is parallel to a side arm (A), parallel to the opposite arm 16 of a side arm (B), +45° to a side arm (C), and -45° to a side arm (D) are wound onto the side of a taper-shaped mandrel so that the upper bottom 12 side is turned to the small diameter side of the mandrel, and a side arm 10 is made parallel to a generating line making the side of the mandrel to form a tapered cylindrical uncured prepreg molding, and the molding is cured by heating. Winding start positions are preferably made different by a half-round between the prepregs (A) and (B) and between the prepregs (C) and (D).