Abstract: In order to realize that the multilateral boreholes can be extracted either synchronously or separately,verify the adaptability of TAML5 lateral well technology in the complex geological environment of Shengli Oilfield,a TAML5 lateral horizontal well was deployed in He 3 Block of Shengli Oilfield,which requires complicated techniques,sophisticated operations,precise control of both wellbore trajectory and its diameter (HD) enlargement rate,difficulties in using complex liner and the high quality sealing between borehole connector and tie-back of the upper branch well.Due to its difficult construction and high demands in drilling and completion process,detailed technical guidelines for drilling and completion measures were proposed.After using synthetical geosteering drilling,optimal wellbore trajectory,casing windowing and sidetracking,gyro orientors,anti-collision,management of HD expansion rate and stable borehole techniques,the lateral well was successfully completed,which provided valuable experience in application of TAML5.In this paper,we will introduce the project plans,analyze technical difficulties,guidelines of drilling and completion,and explain completion processes in details.