The horizontal section of the horizontal well in Daniudi and Dongsheng gas fields in northern Ordos is between 1000~2000m， and inclination-hold drilling is dominated. In order to ensure the inclination-maintaining effect， reduce the frequency of trajectory adjustment and reduce the slide drilling footage， the drilling assembly with the double stabilizers for inclination maintaining was mainly used to keep the inclination， and achieved good effect. However， the tight sandstone reservoirs in northern Ordos is highly heterogeneous， and the horizontal section often cuts through mudstone interlayers to make it necessary to adjust the trajectory， which led to the low build rate of the BHA assembly with the double stabilizers for inclination in the trajectory adjustment； thus， quick adjustment cannot be made to achieve the geological purpose. With analysis of the performance of different BHAs， the variable diameter stabilizers were applied to control their downhole working conditions. Through change of the outer diameter， they can change the drilling string， and its structure and effect to meet trajectory control， and realize inclination drilling along the whole horizontal section with quick and flexible trajectory adjustment. In Daniudi and Dongsheng gas fields in northern Ordos， the variable diameter stabilizers were applied to more than 10 wells in horizontal section drilling with the average ROP of 10.18m/h， and an increase of 24.6% in drilling rate for the horizontal section. The field results were good with improved drilling efficiency at horizontal sections， and can provide beneficial reference for improving drilling speed and efficiency at long horizontal section drilling in Ordos Basin.