Abstract: In order to investigate the impact of slippage on gas drainage in directional boreholes within coal seams, this study utilizes multi-physical field coupling software to establish a two-dimensional simulation of gas drainage and explores the variations in gas pressure, coal seam permeability, and gas production under conditions of gas-solid coupling with consideration for slippage effects, without consideration for slippage effects, and only considering gas migration.Subsequently, a field test is conducted at the No.1 coal seam of ZF219 working face.The results indicate that after 100 days of simulated drainage, the coal seam gas pressure decreases to below 0.5×10⁶ Pa, representing a reduction by approximately 72.22% from its initial level.When considering slippage effects in the context of gas-solid coupling, the coal seam experiences relatively low gas pressure levels alongside significant dynamic changes in permeability and higher levels of gas production; when not considering slippage effects in the context of gas-solid coupling or only focusing on gas migration, changes are not obvious compared to those observed with slippage considerations.The total amount of drained gases from drilling site No.1 ranges between 3 796 m³ and 12 456 m³ with an average drainage volume reaching 8 330 m³ marking an increase of 4.36 times and demonstrating remarkable improvements in drainage efficiency.