A yarn winding machine for winding a yarn (Y) to form a package (P), comprising: a winding mechanism which winds the yarn (Y); and a traverse mechanism which traverses the wound yarn (Y), wherein the traverse mechanism includes: a drive unit which generates a rotation of a drive shaft , a crank portion which converts the rotation of the drive shaft of the drive unit into a rotation of a circular orbit, and a rotary reciprocating conversion portion which converts the rotation of the circular orbit of the crank portion into a reciprocating motion, wherein the crank portion includes: a first power transmission portion which rotates while being connected to the drive shaft and transmits power of the drive unit , and a second power transmission portion which transmits power to the rotary reciprocating conversion portion , wherein a distance between a rotation axis (Ax) of the first power transmission portion and the second power transmission portion is changeable, and wherein the rotary reciprocating conversion portion includes a traverse guide locking the yarn (Y), wherein the yarn winding machine further comprises a changing device which changes a distance between the rotation axis (Ax) of the first power transmission portion and the second power transmission portion , characterized in that the yarn winding machine further comprises a control device which is a processor provided with an integrated circuit or a computer system equipped with said processor and controls an operation of the changing device , so that a traverse width is changed at a desired timing. a winding mechanism which winds the yarn (Y); and a traverse mechanism which traverses the wound yarn (Y), wherein the traverse mechanism includes: a drive unit which generates a rotation of a drive shaft , a crank portion which converts the rotation of the drive shaft of the drive unit into a rotation of a circular orbit, and a rotary reciprocating conversion portion which converts the rotation of the circular orbit of the crank portion into a reciprocating motion, a drive unit which generates a rotation of a drive shaft , a crank portion which converts the rotation of the drive shaft of the drive unit into a rotation of a circular orbit, and a rotary reciprocating conversion portion which converts the rotation of the circular orbit of the crank portion into a reciprocating motion, wherein the crank portion includes: a first power transmission portion which rotates while being connected to the drive shaft and transmits power of the drive unit , and a second power transmission portion which transmits power to the rotary reciprocating conversion portion , a first power transmission portion which rotates while being connected to the drive shaft and transmits power of the drive unit , and a second power transmission portion which transmits power to the rotary reciprocating conversion portion , wherein a distance between a rotation axis (Ax) of the first power transmission portion and the second power transmission portion is changeable, and wherein the rotary reciprocating conversion portion includes a traverse guide locking the yarn (Y), wherein the yarn winding machine further comprises a changing device which changes a distance between the rotation axis (Ax) of the first power transmission portion and the second power transmission portion , characterized in that the yarn winding machine further comprises a control device which is a processor provided with an integrated circuit or a computer system equipped with said processor and controls an operation of the changing device , so that a traverse width is changed at a desired timing. <EOS>