A yarn winding system comprising: a spinning frame configured to form a yarn supply bobbin; and an automatic winder configured to wind yarn from the yarn supply bobbin to form a package, wherein the spinning frame includes an output unit configured to output winding information related to a winding state of the yarn in the formed yarn supply bobbin, the automatic winder includes: an acquisition unit configured to acquire the winding information from the spinning frame; a winding unit configured to unwind the yarn from the yarn supply bobbin and wind the unwound yarn; and a control unit configured to control winding operation of the winding unit, and the control unit determines a winding speed of the yarn in the winding unit, based on the winding information acquired by the acquisition unit, characterized in that the winding information includes information indicating pitch of winding of the yarn in the yarn supply bobbin, information indicating tightness of winding of the yarn in the yarn supply bobbin, and information indicating yarn tension during winding of the yarn in the yarn supply bobbin, and in that the automatic winder is adapted to set the winding speed to a first reference speed or higher when pitch of winding of the yarn is equal to or greater than a first reference value, and sets the winding speed to less than the first reference speed when pitch of winding of the yarn is less than the first reference value, and the automatic winder sets the winding speed to a second reference speed or higher when tightness of winding of the yarn is equal to or greater than a second reference value, and sets the winding speed to less than the second reference speed when tightness of winding of the yarn is less than the second reference value, and the automatic winder sets the winding speed to a third reference speed or higher when yarn tension is equal to or greater than a third reference value. a spinning frame configured to form a yarn supply bobbin; and an automatic winder configured to wind yarn from the yarn supply bobbin to form a package, wherein the spinning frame includes an output unit configured to output winding information related to a winding state of the yarn in the formed yarn supply bobbin, the automatic winder includes: an acquisition unit configured to acquire the winding information from the spinning frame; a winding unit configured to unwind the yarn from the yarn supply bobbin and wind the unwound yarn; and a control unit configured to control winding operation of the winding unit, and an acquisition unit configured to acquire the winding information from the spinning frame; a winding unit configured to unwind the yarn from the yarn supply bobbin and wind the unwound yarn; and a control unit configured to control winding operation of the winding unit, and the control unit determines a winding speed of the yarn in the winding unit, based on the winding information acquired by the acquisition unit, characterized in that the winding information includes information indicating pitch of winding of the yarn in the yarn supply bobbin, information indicating tightness of winding of the yarn in the yarn supply bobbin, and information indicating yarn tension during winding of the yarn in the yarn supply bobbin, and in that the automatic winder is adapted to set the winding speed to a first reference speed or higher when pitch of winding of the yarn is equal to or greater than a first reference value, and sets the winding speed to less than the first reference speed when pitch of winding of the yarn is less than the first reference value, and the automatic winder sets the winding speed to a second reference speed or higher when tightness of winding of the yarn is equal to or greater than a second reference value, and sets the winding speed to less than the second reference speed when tightness of winding of the yarn is less than the second reference value, and the automatic winder sets the winding speed to a third reference speed or higher when yarn tension is equal to or greater than a third reference value.