To provide a weft cutter with which a weft is surely cut and which has excellent durability.

A controller 32 grasps the rotation position of an output shaft 221 on the basis of the detected information of rotation position from a rotation position detector 26 and calculates the rotational speed of the output shaft 221. The controller 32 grasps the rotation angle of the weaving machine based on the detected information of the rotation angle of the weaving machine from the rotation angle detector 33 of the weaving machine. The controller 32 carries out command control of current supply to a rotary solenoid 22 on the basis of these understandings. The controller 32 calculates the rotational speed of the output shaft 221 when the rotation position is in a fixed range. When the rotational speed is a fixed rotational speed or lower, the controller 32 increases a current supply value.