Abstract: Based on existing technical problems in horizontal drilling with gas, single-stabilizer BHA with rotary drilling is used to solve problems of angle holding during drilling of horizontal sections with gas. Theoretical simulation analysis is conducted with locale practices, laying basis for further study on horizontal drilling with gas. According to field test conditions, the crossbar bent continuous beam theory is applied. The effect of some parameters on trajectory’s drilling tendency is analyzed, such as the position and diameter of stabilizer, borehole diameter and WOB. The simulation result indicates that the trajectory control effect is sensitive to such parameters as the position and diameter of stabilizer, WOB and the hole enlargement ratio with the single stabilizer BHA and gas drilling in horizontal wellbore. The locale practice indicates that the application of single stabilizer BHA with gas drilling in horizontal wellbore could reach trajectory controlling aim under present technical and instrument conditions. The trajectory drilling tendency analysis focusing on actual application conditions is the basis for effectively utilizing this technology.