This paper focuses on the research and applied technology at the first extra-deep  exploration well in centre Asia region, which is located in Fergana Basin and operated by CNPC with a final depth of 6 559 m and a couple of pay zones in the interval of 5 800~6 596 m were discovered in 2009. This extra deeper well borehole with a critical high temperature of 147 ℃ and high pressure of 135 Mpa in the pay zone formation. Successful achievements in drilling engineering technical aspects are summaried in this paper.