Abstract: In order to realize accurate connection of two horizontal wells, a magnetic field ranging steering tool was introduced, and research was conducted on the design of U-shaped horizontal wellbore profile. While conducting uncertainty analysis of wellbore trajectory, a composite error circle was introduced. By comparing the diameter of the composite error circle with the ranging size of the magnetic field ranging steering tool, the timings for using two magnetic ranging steering tools were obtained. Based on the selection and use of the magnetic ranging steering tool and measuring characteristics, the relevant wellbore profile was designed. The additionally extended part was the key part in profile design, and its accurate calculation equation was given by the ranging size. Example verification shows that this profile design is reasonable. The U-shaped horizontal well profile design reflects the integration of drilling design with control, providing reference significance for further study and practice in the future.