To smoothly, precisely and efficiently remove the gill from squid after removing the legs and guts just after the capture by cutting and dividing treatment in a ship, and further facilitate the grading and packing operations after the removal.

This apparatus for treating a squid has rapidly rotating eccentric rolls 3 installed on a conveying belt 1 of the cut and opened squids after removing the legs and guts to spread and reshape the squids to the cut and opened state by the beating and pressing action thereof, belt-supporting rolls 5 for forming wave-like surfaces on the conveying belt, and brush rolls 6 slidably turning at the concave parts of the wave-like surface to remove the gills attached to the squids.