The invention discloses a work method of a high-precision plastic plate grabbing mechanism. The high-precision plastic plate grabbing mechanism comprises a material containing bucket body, a materialcontaining inner cavity is formed in the middle of the material containing bucket body, a vertical through groove is formed in the inner side wall of the material containing inner cavity, a lifting air cylinder is fixed to the outer side wall of the lower portion of the material containing bucket body, supporting plates are fixed to the two opposite outer side walls of the material containing bucket body, an upper connecting plate is fixed to the two supporting plates, the top face of the upper connecting plate is fixedly provided with a rodless air cylinder, a moving block of the rodless aircylinder is inserted in a transverse through groove in the middle of the upper connecting plate in a sleeved manner, the lower end of the moving block extends out of the upper connecting plate downwards and is fixedly provided with a vertical fine adjustment motor, an adjusting rod is in screw joint into a screw joint hole in the middle of the bottom face of a rotating shaft of the vertical fine adjustment motor, a vacuum suction cup is fixed to the lower end of the adjusting rod, and is located over the material containing bucket body, a guide rod is fixed to the bottom face of the moving block, and a vertical inserting hole is formed in the middle of the bottom face of the guide rod. Plastic plates can be automatically grabbed, feeding is facilitated, and production efficiency is improved.