Abstract: In order to improve the ROP and reduce the deviation angle in Yinzhubu Formation during the 2nd spud section of Well Xuanye 1,a new 311.1 mm six blade PDC bit was designed with better stability,abrasion resistance and deviation reduction.The design took small cone angle and shallow cone crown,short gauge,short joint structure,high density distribution of teeth and hard alloy limited damping teeth.The designed PDC bit was applied with the auto-vertical drilling system in the section of 805.61-1 017.18 m in Well Xuanye 1,resulting in the average ROP of 3.28 m/h,which was 8.61% higher than the conventional PDC bit.The minimum deviation angle of 1.09° was much smaller than that of conventional PDC bit,putting well deviation under good control.Field application indicated that the designed new PDC bit showed good performance in deviation control,stability and rock cutting effects,meeting the requirements of deviation control and fast drilling.