The invention provides a cylinder end face drilling special fixture and belongs to the technical field of machining. Through the cylinder end face drilling special fixture, the problems that the requirements for quantity production cannot be met, the machining precision is low and the product qualified rate is low when a locating hole is drilled in one end face of a cylinder workpiece through a scribing drilling method in the prior art are solved. A mounting hole and a locating deep slot are vertically formed in a fixture body from top to bottom. A drill bush is penetrated into the mounting hole. The locating deep slot is an arc-shaped slot. The slot bottom is horizontally arranged. The fixture body is provided with a long hole. The symmetrical center line of the long hole is horizontallyarranged from front to back. The upper and lower sidewalls of the long hole communicate with the mounting hole and the slot bottom of the locating deep slot correspondingly. A threaded hole is horizontally formed in the front portion of the fixture body. The threaded hole communicates with the front sidewall of the locating deep slot. The sidewall of the workpiece is inserted in the locating deepslot. The vertical distance from the center axis of the mounting hole to the rear sidewall of the locating deep slot is equal to the distance from the locating hole of the cylinder workpiece to the edge of an inner hole of the cylinder workpiece. The cylinder end face drilling special fixture is used for drilling of the end face of the cylinder workpiece.