Machining method for precision holes in narrow area

The invention relates to a machining method for precision holes in a narrow area. The method comprises the steps that an inner rib positioning hole is machined in an inner rib of a workpiece, an outer rib positioning hole and an operating hole are machined, and the inner rib positioning hole, the outer rib positioning hole and the operating hole are coaxial; linings are pressed into the holes; machining is conducted with the outer rib lining hole serving as a positioning reference; and finally machining is finished. According to the technology method, the technical problems that the precision holes are manufactured in advance in a workpiece state, and consequently installing and positioning are not accurate, and inner hole surface treatment protection is needed can be effectively solved, the machining method is suitable for manufacturing of key stress structural pieces of an airplane, and the machining precision and efficiency of the installing and positioning holes are greatly improved.