Abstract: Design of track control of inclination interval and drill stem is most important in drilling operations of directional and horizontal wells. This paper found a solution of deformations of all the three segments of drill stem-the bent, the suspended and the connecting one between the bent and straight sections taking considerations of the bent beam model of the three generalized displacements and the two generalized displacements under condition of existence of gap between drill stem and borehole wall. By means of example calculations and the concrete analysis on borehole gauge and inclination data obtained in RP- 2 wel1, the paper examined the reasonableness and correctness of the calculation method and created a basis for correct design of borehole track and drill stem composition.