Abstract: In the target layer of the deep coal rock gas horizontal well in the eastern gas field of Ordos Basin, the 8^# coal seam of the Benxi Formation is deeply buried and has strong heterogeneity. During the drilling process, there are technical difficulties such as low rate of penetration (ROP), easy instability and collapse of the wellbore, complex and frequent downhole faults, difficult extension of the horizontal section, and challenging completion casing running. Therefore, on the basis of analyzing the characteristics of the 8^# coal seam of the Benxi Formation and technical difficulties during drilling, the optimization of high-efficiency PDC bit and speed-up tool for reverse reaming, optimization of steering drilling tool assembly without stabilizer for sticking prevention, fine steering trajectory control technology for horizontal sections, rotary casing running technology, and micro-nano strong inhibition of high-efficiency water-based drilling fluid system technology were conducted, and key technologies for safe drilling in horizontal sections of deep coal rock gas horizontal wells in Ordos Basin were developed. The technologies were applied to 10 deep coal rock gas horizontal wells in the Suide–Mizhi Block of the eastern gas field of Ordos Basin. No downhole faults such as wellbore instability occurred in the drilling process of horizontal sections, and the wells were successfully drilled to the designed completion depth. The casing was smoothly run to the designed position, with an average ROP of 9.00 m/h, indicating a 48.51% increase compared with the adjacent Well NL1H without the technologies applied. Field applications show that the key technologies for safe drilling in horizontal sections of deep coal rock gas horizontal wells in Ordos Basin can overcome the technical difficulties in the drilling process of horizontal sections of deep coal rock gas horizontal wells in the eastern gas fields of the basin, improve the mechanical drilling rate of the horizontal sections and the drilling rate of the coal rock reservoir, and provide technical support for the development of deep coal rock gas in the basin.