The invention discloses a vacuum laser processing device which comprises a housing; one end of the housing is in sealing connection with an end cover; a laser device and a workbench are arranged in an inner cavity of the housing; the laser device is located above the workbench; a vacuum orifice is formed in the upper surface of the housing, and is connected with a vacuum pump through a pipeline; a pressure gauge for detecting the vacuum degree of the inner cavity of the housing is arranged on the housing; a portal frame is arranged on the upper surface of the inner wall of the housing; a carrying plate is arranged at the portal frame; the laser device is arranged on the lower surface of the carrying plate; and a window is formed in the side wall of the housing. The vacuum laser processing device is simple in structure, reasonable in design and convenient to operate; the laser device can move forwardly, reversely, leftwards and rightwards, and carries out operation on a workpiece on the workbench in an omnidirectional manner; and the vacuum pump is high in vacuumizing speed and good in vacuumizing effect, and the processability of laser is improved.