The crawler drilling rig adopts full hydraulic driving, traveling with crawlers itself. The drill head is driven by variable motor with function of two-speed mechanical gear shifts, stepless speed change with an advanced and simple structure. The rotator is fed and driven with a system connecting the spindle and oil cylinder with chain. The system has the function, if the piston rods of oil cylinder moving one certain distance, the drill head moving will double the distance. The mast could be adjusted within the range of angle 0 to 90 degree for its drilling hole with a low center of gravity and good stability of the overall unit. The crawler drilling rig provides operator with a nice field of vision and wide and comfortable working condition. The hydraulic crawler drill rig looks pretty in overall structure and embodies the design thought of people oriented.