The utility model provides a track rig substructure levelling mechanism, its characteristics are including track rig substructure, do not establish two pneumatic cylinders in the punishment of track rig substructure's lower bottom four corners, and the piston rod head of every pneumatic cylinder is spherical, and describe for the ball socket on the support upper portion of piston rod. Still establish four screw jack respectively in track rig substructure's lower bottom four corners department, every screw jack's lead screw tip is the bulb, and describe for the ball socket on screw jack's support upper portion. The utility model discloses the height in whole each position of rig floor of speed adjusting makes the rig floor face recover the level soon to do not influence the rig in the adjustment procedure and normally work, improved the rig security performance, ensured going on smoothly of production.