Abstract This paper describes the difficulties in the construction of YM7-H1 well which is the first horizontal well in Yingmaili of Xinjiang,and presents the construction process of each well phase,technology measures and well course control methods. This research provides construction experience for the drilling of complicated horizontal wells with high-density drilling fluid,ultra-deep large-size boreholes and the exploration of the deep reservoir in Yingmaili of XinJiang.