Abstract: : In order to improve the prospecting benefit,shorten drilling cycle and save drilling cost in deep tight glutinite gas reservoirs in Daqing Oilfield,the research on horizontal slim-hole drilling had been carried out.Firstly,according to the principle that allowable casing bent radius must be less than the actual bent radius of wellbore,and the casing program was optimized on the basis of analyzing the possibility that running φ177.8 mm intermediate casing in φ215.9 mm curved wellbore safely,and the φ152.4 mm BHA passed through φ177.8 mm intermediate casing.Secondly,as the depth of target pay zone may be shallower or deeper than that of prediction,hold angle formula was used to calculate the hold angle of reservoirs in different thickness,in addition,taking the formation deflecting ability and borehole size into account in build up section,the well trajectory was optimized.Finally,according to the features of formations,the type of drill bit,bottom-hole assembly and drilling parameters were optimized,the horizontal slim-hole drilling technology had been formed for deep tight glutenite gas reservoirs in Qingshen Gas Field.The application of this technology in Well Xushenping 3X led to a reduction of drilling cycle time of 32.83% than conventional horizontal well method,it provides new technical means for exploration and development in deep tight glutenite gas reservoirs.