Abstract: In a line cutting device of the type adapted to be mounted on the propeller shaft of a water-borne vessel for the purpose of cutting lines, ropes, nets, plastic bags or other debris which may foul the blades of a propeller on the shaft, a stationary cutting blade assembly is mounted so as to be restrained against rotation by cooperation with a shaft bearing. The stationary cutting blade assembly having a radially extending stationary cutting blade with an axially directed face and at least one circumferentially directed face defining a cutting edge therebetween. A rotatable cutting blade assembly is mounted for rotation with the propeller shaft and has at least one radially extending rotatable cutting blade thereon with an axially directed face and at least one circumferentially directed face defining a cutting edge therebetween.