To provide a yarn winding machine capable of accurately acquiring a yarn speed immediately after starting winding.

A spinning machine as a yarn winding machine includes winding devices 13, spinning devices 9, a rotary encoder mechanism, a yarn splicing device 43, a seam monitor 47 and a carriage control part. The winding devices 13 each wind up a spun yarn 10 around a package 45. The spinning devices 9 each feed the spun yarn 10 to the winding device 13. The rotary encoder mechanism detects a rotation speed of the package 45. The yarn splicing device 43 forms a seam 99 by splicing the spun yarn 10 between the spinning device 9 and the package 45. The seam monitor 47 is disposed on a downstream side of the yarn splicing device 43 in a running direction of the spun yarn 10 and monitors the seam. The carriage control part determines whether the seam formed by the yarn splicing device 43 is normal or not on the basis of on the running speed of the spun yarn 10 obtained on the basis of the detection result of the rotary encoder mechanism and the monitoring result by the seam monitor 47.