A tube end molding method comprising: a tube shrinking step for molding one end of an original tube , in which a tapered portion having a diameter decreasing toward a tube end and a small diameter tube portion continuing from a small diameter side of the tapered portion to the tube end and having a diameter substantially the same as a diameter of the small diameter side are formed at the one end of the original tube ; a preparing step for preparing a holding die including: an original tube bore that holds the original tube ; and an tube expanding bore formed to continue to the original tube bore via a tapered portion and having an inner diameter greater by a predetermined value than an outer diameter of the original tube ; and a tube expanding step including: a first step for mounting the original tube into the original tube bore so that at least a part of the tapered portion is housed in the tube expanding bore ; a second step for folding the small diameter tube portion inside the original tube beginning at the tapered portion by depressing the small diameter tube portion in an axial direction with a punch member ; and a third step for moving the punch member further in the axial direction after folding the small diameter tube portion , inserting a tapered portion and a tube expanding portion of the punch member into an inside of a folded portion of the original tube , and pressing the folded portion against an inner wall of the tube expanding bore . a tube shrinking step for molding one end of an original tube , in which a tapered portion having a diameter decreasing toward a tube end and a small diameter tube portion continuing from a small diameter side of the tapered portion to the tube end and having a diameter substantially the same as a diameter of the small diameter side are formed at the one end of the original tube ; a preparing step for preparing a holding die including: an original tube bore that holds the original tube ; and an tube expanding bore formed to continue to the original tube bore via a tapered portion and having an inner diameter greater by a predetermined value than an outer diameter of the original tube ; and a tube expanding step including: a first step for mounting the original tube into the original tube bore so that at least a part of the tapered portion is housed in the tube expanding bore ; a second step for folding the small diameter tube portion inside the original tube beginning at the tapered portion by depressing the small diameter tube portion in an axial direction with a punch member ; and a third step for moving the punch member further in the axial direction after folding the small diameter tube portion , inserting a tapered portion and a tube expanding portion of the punch member into an inside of a folded portion of the original tube , and pressing the folded portion against an inner wall of the tube expanding bore . a first step for mounting the original tube into the original tube bore so that at least a part of the tapered portion is housed in the tube expanding bore ; a second step for folding the small diameter tube portion inside the original tube beginning at the tapered portion by depressing the small diameter tube portion in an axial direction with a punch member ; and a third step for moving the punch member further in the axial direction after folding the small diameter tube portion , inserting a tapered portion and a tube expanding portion of the punch member into an inside of a folded portion of the original tube , and pressing the folded portion against an inner wall of the tube expanding bore . <EOS>