Takes glass fiber reinforced resin matrix composite and its composite stepped hole as the research objects, through performance analysis, tooling and tool design, process parameters optimization, the influence of various factors on the stepped hole is studied. The experimental results show when the pre pressure stress is applied to the material of the drilling area by using the 25 degree (helix angle)/15 degree (rear angle) of the alloy composite bit, the processing quality of the hole is best under the speed of the bit is 250 or 315 r/min, the feed rate of the bit is 0.06 or 0.1 mm/r.