A laser cutting device includes: a main body configured to emit a laser beam, a cutting point being formed at a position where the laser beam intersects a material to be cut; a gas blow pipe, of which a gas blow mouth configured to blow out a gas flow that is inclined to the laser beam, the gas flow capable of aiming at the cutting point; a gas suction pipe, of which a gas suction mouth being located downstream of a flowing direction of the gas flow, relative to the cutting point; the gas blow pipe and the gas suction pipe being attached respectively to the main body by means of an adjustment mechanism, such that positions of the gas blow pipe and the gas suction pipe are adjustable to adapt to change of a laser beam cutting route.