Abstract: To address the challenges of limited mining height, confined space, uneven floor conditions, high labor intensity, and significant safety risks in thin coal seam fully mechanized longwall faces, a quadruped inspection robot tailored for such complex environments is proposed, with particular emphasis on the design and simulation-based analysis of its walking mechanism. The robot can walk, cross obstacles, and climb slopes, featuring a lightweight and modular structure. Explosion-proof servo motors are centrally mounted on the main body to effectively reduce moving inertia and enhance overall stability. The walking mechanism comprises explosion-proof motors, linkage-type legs, a gear-shifting device, and a transmission system. A kinematic model of the leg mechanism is developed to investigate the influence of crankshaft mounting position on leg performance. Taking lift height and driving torque as optimization objectives, a multi-objective optimization model is formulated and solved using the NSGA-II algorithm in MATLAB. This yields high-performance installation regions and optimal mounting points for two distinct leg-lifting modes. To validate the walking mechanism’s performance, a virtual prototype of the quadruped robot and a 3D model of a thin coal seam longwall face are constructed. Dynamic simulations of the robot’s machine-following inspection process are performed in ADAMS. The results demonstrate that the robot reliably executes predefined gaits and exhibits excellent dynamic stability across four operational scenarios: level walking, obstacle crossing, slope climbing, and combined slope-climbing with obstacle traversal. It achieves a maximum obstacle-crossing height of 118 mm, a maximum walking speed of 15.6 m/min, and a maximum climbing angle of 10°, fully satisfying the requirements for machine-following inspection in thin-seam longwall operations. This work provides a practical foundation for advancing minimally manned and intelligent mining in thin coal seam fully mechanized faces.