To provide a laver foreign matter removing machine of small size having a great capacity of foreign matter removal, capable of surely removing a foreign matter.

This machine is equipped with a separation vessel 5 at the bottom of a feed tank 1 and a pair of gap-forming members 8 and 9 opposing to division zones for dividing the inside of the feed tank 1 and that of the separation vessel 5. One of the gap-forming members 8 and 9 is provided with a ring-shaped hole 18A and the other is concentrically furnished with a ring- shaped wall 28A to be superimposed on the ring-shaped hole 18A observed in a plain view. Gap lines 20A are formed at both edge parts of the ring-shaped wall 28A. One of the gap-forming members is made relatively rotatable to the other and is adjustable at a relative position in the direction of rotation axis.