The Qiongzhusi formation and Dengying formation of Datachang structure have good source-reservoir-cap assemblages with great potential for the exploration and development of oil and gas reservoirs. But the geological conditions in this area are complicated, during the upper formation drilling, serious leakage of Shaximiao formation, poor drillability of Xujiahe formation and some other difficulties were found. In order to speed up the drilling process in this block and solve the technical difficulties which restricted the drilling speed, by the analysis on the drilling data of the early drilling & completion and the present drilling situation, the technical difficulties probably being encountered in the drilling of upper formation of Datachang structure are clarified. According to the field practice, the technical measures of initial well deviation prevention method, large size casing cementing technology, gel cement plugging technology, bit selection are put forward, which can be guidance in drilling and cementing construction in this block.