Abstract: To increase the rate of penetration in drilling horizontal wells and prepare for later reinforced reservoir stimulation in Sulige Area,drilling engineering design of Well Su 25-2-2H was optimized.Firstly,according to the formation characteristics to be drilled and the development requirements,the well profile was optimized into a two-section in "vertical-buildup-adjustment"type by using the Plan Editor Module of Compass.Secondly,BHA(bottom hole assembly)for vertical section,inclined section and horizontal section were optimized.Thirdly,to meet the requirement of site operation,the strength of drilling string and casing was verified by using the Module of Wellplan.Finally,the KCl drilling fluids,with good inhibition and rheological property and the PDC drilling bit were optimized to match the rock features and formation pressure.Field application showed that drilling rate increased by 24.61%,and the drilling cycle time reduced by 30.79% after optimization of well profile.The successful drilling of Well Su 25-2-2H has provided more options in completion and stimulation modes.