To provide a cutting device capable of cutting an object to be cut in such a state that it is grasped by a grasping member.

This cutting device 8 can be attached to and detached from a shovel-system excavator etc. and make cutting of the object to be cut as grasped. In addition, the device 8 includes: a pair of body frames 14 which are connected with the apex part of an arm of the shovel-system excavator and equipped with a receiving part 14a for receiving the object; a movable blade 15 which is pivoted at the body frame 14 in vertically rocking manner, relatively to the receiving part 14a; a cutting hydraulic cylinder 16 designed for driving the movable blade 15 in rocking fashion; a grasping member 17 which is pivoted at the body frame 14 in vertically rocking fashion, relatively to the receiving part 14a, and can grasp the object in collaboration with the receiving part 14a; and a grasping hydraulic cylinder 18 for driving the grasping member 17. Besides, the body frame 14 is rotatably supported at the apex part of the arm by a rotary support mechanism, and is rotatably driven in the normal and reverse directions by a rotary driving part.