Abstract: In order to reduce drilling cost, reduce downhole accidents and realize economic and effective development of oil/gas reserves, experimental research was conducted on surface casing drilling technology in Karamay Oilfield. In line with the geologic features of the oilfield and self development of process and tool equipment, research was conducted on casing drilling technology and auxiliary drilling tool techniques. The casing hanger and reamer while drilling were developed and were tested in four wells in Hongshanzui Oilfield in Junggar Basin in Xinjiang, which was very successful. The average penetration rate was increased by 92.2% compared with conventional drilling, which proves that casing drilling technology, after being improved, and achieved the goals of reducing drilling cost and improve economic benefits. So the technology has a broad development prospect.