Abstract: For the purpose of using large-diameter precision composite sand filtrate tube completion technology to liberate reservoir and increase drainage area as much as possible,a well Z18-ZP1 was deployed in Shengli oilfield. It's the first heavy oil thermal recovery horizontal branch well in Shenglioilfield. Heavy oil thermal recovery fish-bone shaped horizontal branch well drilling technique has special drilling technology and higher requirement for drilling fluid and completion fluid. Based on the analysis of technology difficulty,this paper has discussed in detail the well structure,drillingmode,open-hole sidetracking,bottom hole assembly,drilling fluid,completion fluid and application effects of well Z18-ZP1. The success of Z18-ZP1 has accumulated valua-ble experience for heavy oil thermal recovery horizontal branch well technology in shengli oilfield.