The utility model discloses a shielding case compatible sucking and assembling mechanism based on a vacuum principle. The device comprises a telescopic power piece, a sucker set installation piece isinstalled at the output end of the telescopic power piece, more than one sucker assembly is fixedly installed on the sucker set installation piece and driven by the sucker set installation piece to dotelescopic motion, each sucker assembly comprises a sucker, and the top of each sucker is sleeved with a spring. According to the utility model, the limitation and incompatibility that suction pointsare not in the same plane when a product is sucked can be quickly and effectively solved, the production efficiency is effectively improved, and the cost is saved.