A yarn winding machine comprising: a plurality of winding units, each of the winding units configured to unwind a yarn from a yarn supplying bobbin and to wind the unwound yarn into a package; a bobbin processing device configured to perform a pre-processing on the yarn supplying bobbin that is mounted on a tray, and to collect the tray on which an empty bobbin from which the yarn has been unwound in the winding unit is mounted; a tray transporting device configured to transport the tray between the winding units and the bobbin processing device; and a control device (51 to 56), wherein the tray transporting device includes a supply path configured to transport a tray on which the yarn supplying bobbin has been mounted to the winding units; a collection path configured to transport a tray that has been discharged from the winding units to the bobbin processing device; a return path configured to transport a tray that has been transported to a downstream end of the supply path so as to be returned to an upstream end of the supply path; a conveyor device configured to transport a tray along the supply path, the collection path, and the return path; and a tray controlling device arranged on the return path and configured to send a tray present on the return path to the upstream end of the supply path, the bobbin processing device configured to supply the tray to any one of the supply path and the return path, and the control device (51 to 56) configured to cause the tray controlling device to perform a sending operation of sending the tray at a first sending pace that corresponds to a difference between a pace at which the trays are discharged from the winding units to the collection path and a pace at which the trays are supplied from the bobbin processing device directly to the supply path or to a portion in the return path that is downstream than the tray controlling device. a plurality of winding units, each of the winding units configured to unwind a yarn from a yarn supplying bobbin and to wind the unwound yarn into a package; a bobbin processing device configured to perform a pre-processing on the yarn supplying bobbin that is mounted on a tray, and to collect the tray on which an empty bobbin from which the yarn has been unwound in the winding unit is mounted; a tray transporting device configured to transport the tray between the winding units and the bobbin processing device; and a control device (51 to 56), wherein the tray transporting device includes a supply path configured to transport a tray on which the yarn supplying bobbin has been mounted to the winding units; a collection path configured to transport a tray that has been discharged from the winding units to the bobbin processing device; a return path configured to transport a tray that has been transported to a downstream end of the supply path so as to be returned to an upstream end of the supply path; a conveyor device configured to transport a tray along the supply path, the collection path, and the return path; and a tray controlling device arranged on the return path and configured to send a tray present on the return path to the upstream end of the supply path, a supply path configured to transport a tray on which the yarn supplying bobbin has been mounted to the winding units; a collection path configured to transport a tray that has been discharged from the winding units to the bobbin processing device; a return path configured to transport a tray that has been transported to a downstream end of the supply path so as to be returned to an upstream end of the supply path; a conveyor device configured to transport a tray along the supply path, the collection path, and the return path; and a tray controlling device arranged on the return path and configured to send a tray present on the return path to the upstream end of the supply path, the bobbin processing device configured to supply the tray to any one of the supply path and the return path, and the control device (51 to 56) configured to cause the tray controlling device to perform a sending operation of sending the tray at a first sending pace that corresponds to a difference between a pace at which the trays are discharged from the winding units to the collection path and a pace at which the trays are supplied from the bobbin processing device directly to the supply path or to a portion in the return path that is downstream than the tray controlling device.