The invention provides a pneumatic type jig drilling device of end cover pieces and belongs to the field of automatic industrial production. The pneumatic type jig drilling device is composed of an air cylinder, an air cylinder installation plate, an inclined wedge, a support, a workpiece installation plate, a base plate, an arc-shaped link rod, a pressing plate, a first positioning plate, a positioning pin and a second positioning plate; the pressing plate is formed by a pressing plate link rod and a steel ball, the end cover pieces are automatically positioned by the positioning pin, the first positioning plate and the second positioning plate, and the inclined wedge is driven by the air cylinder to move in a straight line; when the inclined wedge reach a certain position, the arc-shaped link rod is jacked up, and then the tail portion of the pressing plate link rod is jacked up by the arc-shaped link rod; and through the support, the front portion of the pressing plate link rod moves downwards, so that the steel ball installed on the front portion of the pressing plate link rod moves downwards, and thus, clamping for the end cover pieces is achieved. The pneumatic type jig drilling device of the end cover pieces can sufficiently lower the requirements of workers for technology, and hole drilling efficiency and precision of an end cover are greatly improved.