At present, large displacement horizontal well technology is applied domestic and abroad, thin layer mining puts forward high requirements for drilling quality. 3D geological guidance system can bring intuitive and clear understanding of geological structure to field engineers, so that they can guide drilling production more accurately. The three-dimensional geological guidance system for horizontal wells is being developed, using seismic interpretation results, structural contours, temporary well data to form three-dimensional structural geological bodies, establishing geological guidance model, carrying out wellbore trajectory tracking and oil and gas display analysis near the drilling bit, adjusting the guiding model in real time according to the field operation, guiding the horizontal well drilling construction and prediction analysis in real time, and improving the reservoir drilling rate.