To provide a vane traversing device capable of transporting thread to a rotary vane across a turn-around point during runout of thread to surely prevent winding on a rotor on which the rotary vane is mounted.

A vane traversing device includes a thread guide 1 having a guide plane 1a for forming a traversing track, two rotary vanes 2 arranged up and down in the moving direction of thread and rotated in mutual opposition along the thread guide 1 for delivering the thread Y2 at a turn-around point on the traversing track and a cover member 5 provided around a rotor 25 on which the rotary vane 2 is mounted.