The invention relates to an outer wall vacuum inorganic foam insulation plate and a manufacturing method thereof. The insulation plate is made of a vacuum packaging bag and a foam insulation core plate mounted in the bag; the foam insulation core plate is one of a foam cement plate or a foam glass plate or a foam ceramic plate; the vacuum packaging bag adopts an aluminum foil vacuum packaging bag; construction mounting edges of 15-30 mm are pressed on the two sides or the periphery of the aluminum foil vacuum packaging bag; and the aluminum foil vacuum packaging bag adopts a single-layer aluminum foil vacuum packaging bag or a dual-layer aluminum foil vacuum packaging bag. Due to the insulation plate, the thickness of the outer wall insulation plate can be reduced, the thermal insulation and insulating performance of the insulation plate can be enhanced, the phenomenon of expanded deformation, aging, cracking, damage and the like can be also eliminated, and the service life of a wall body is greatly prolonged. The insulation plate has the advantages of light weight, low heat conducting coefficient, excellent insulation performance, high strength, aging resistance and good fireproofing flame retardant effect.