The invention discloses a clamping mechanism. The clamping mechanism comprises a supporting box, a supporting frame, a first rotating shaft, a second rotating shaft, a clamping drive device, a first clamping claw and a second clamping claw, wherein the supporting frame is arranged on the supporting box; the first rotating shaft and the second rotating shaft are arranged on the supporting frame in a rotating mode and are in transmission connection through a transmission mechanism; the clamping drive device is used for driving the first rotating shaft or the second rotating shaft to rotate; the first clamping claw is fixed to the first rotating shaft; the second clamping claw is fixed to the second rotating shaft. According to the clamping mechanism, the clamping drive device is used for driving the first rotating shaft or the second rotating shaft to rotate and then driving the first clamping claw and the second clamping claw to do opposite movements or separating movements, and therefore the purpose of holding lines or loosening lines can be achieved. When a drive wheel and a clamping wheel cross obstacles, the lines can be clamped through the clamping mechanism, and it can be ensured that an inspection robot will not fall off from the lines. The invention further discloses an inspection robot walking mechanism provided with the clamping mechanism.