Abstract: In order to improve the implementation effect of horizontal wells in East China Sea, in view of the characteristics of large buried depth, thin reservoir thickness, rapid lateral change and complex internal structure in sand bodies, the geological steering technology of horizontal wells was studied, and a set of geosteering strategies and methods suitable. The fine formation correlation is carried out with logging, mud logging and other data while drilling to predict the depth of the target zone in real time and ensure a smooth landing of the appropriate wellbore inclination, for the implementation of horizontal wells in East China Sea were summarized. The geological guidance model is established to guide drilling in the horizontal section, improve the drilling rate of effective reservoirs in the horizontal section, and improve the implementation effect of horizontal wells. The average drilling penetration rate of sandstone and effective reservoir is 80.3% and 74.9% by adopting geosteering technology, which has achieved the remarkable implementation effect, and has high reference and application value for the subsequent implementation of horizontal wells in East China Sea.