To provide a simple thread-pulling prevention device for an automatic winder to prevent a phenomenon called "thread pulling" produced by a state where a bobbin is discharged although thread remains on a thread running path of a winding unit and the bobbin.

The thread-pulling prevention device for the automatic winder is installed in a carrier guide of the bobbin tray-type automatic winder, and comprises a resistance body rotating the bobbin in the thread winding direction during contact with the bobbin and a support part supporting the resistance body.