Abstract: Due to the harsh service environment and complex stress state, mining drill pipe is prone to failure. This will seriously affect normal production and worsen the accident due to salvage difficulties.In this study, the force analysis of drill pipe joints was conducted on Φ73 mm outer-flat directional drill pipes in coal mines under different loads. The mechanical property parameters of the joint material were obtained through uniaxial tensile tests, and the constitutive model of the joint material was constructed. then, the elastic-plastic finite element analysis model of the drill pipe joint thread was established by applying the virtual work principle, Von Mises yield criterion, and contact nonlinear theory to analyze the stress state and stress field distribution of the joint under the action of load under different working conditions. The study demonstrates that the drill pipe joint exhibits satisfactory sealing performance and connection strength at a preload torque of 2000 N?m. The first thread tooth near the main shoulder is identified as the primary failure site under both single torsion and tension torsion loads. Meanwhile, the main shoulder is the principal failure location under compression, bending, and torsion loads. Moreover, under the combined effect of the maximum torque and thrust of the drilling rig, the joint's bending resistance is found to reach 3°/3m.