ABSTRACT Sichuan basin is the primary carbonate deposition basin in China, which is rich in natural oil and gas resources and has a very long drilling history. The geological conditions in the basin are very complex, which causes a lot of difficulties in deep drilling. Since the end of 1970s, with the development of exploration and drilling in deep formation, a series of complicated technical problems in deep and ultradeep drilling have been well solved. During the recent years, a large number of deep wells and some ultradeep wells have been completed. The economic index of drilling technique has been largely improved. This paper foresees the future development of deep drilling technique in Sichuan basin.