The invention relates to a laser three-dimensional scanning device and a laser three-dimensional scanning method. The device comprises a first transmission grating, a second transmission grating, a third transmission grating, a first acoustic optic deflector, a second acoustic optic deflector, a first lens, a first half wave plate, a second lens, a third acoustic optic deflector, a third lens, a second half wave plate, a fourth lens, a fourth acoustic optic deflector and a micro objective, which are arranged along the direction of a light path. The method comprises the following steps: injecting periodical sound waves in the first acoustic optic deflector and the second acoustic optic deflector; and injecting chirped sound waves in the third acoustic optic deflector and the fourth acoustic optic deflector. The device realizes three-dimensional scanning by adopting the four acoustic optic deflectors; and because existing acoustic optic deflectors can completely reach microsecond acousto-optic interaction time, the device can completely realize microsecond quick scanning in XYZ three-dimensional directions.