The invention discloses a pressure sensor inner core lining press-fit tool with a positioning mechanism and a using method, the pressure sensor inner core lining press-fit tool comprises a stand column and a base, transmission boxes are symmetrically arranged on the two sides of the interior of the base, driven bevel gears are arranged on the upper portions of the interiors of the two transmission boxes, and the driven bevel gears are arranged on the upper portions of the interiors of the two transmission boxes; the two driven bevel gears are rotationally connected with the transmission box, stand columns are arranged on the upper portion of the base, lead screws are arranged in the two stand columns, the two lead screws are connected with the driven bevel gears, and sliding rods are symmetrically arranged on the portions, on one sides of the two lead screws, of the base. The device is provided with an air guide pipe, a fixing rod, bubbles and a connector, an inner core lining is conveniently pre-fixed by the device, the problems that the inner core lining deviates during installation, consequently, press fitting is not in place, and a defective product is formed through press fitting are solved, in addition, an electric cylinder, a transmission plate, a connecting rod and a top plate are used in cooperation, discharging of the device is facilitated, and the working efficiency is improved. And the working efficiency of the device is improved.