Abstract: The present invention is a portable drilling rig having a support tower. A drilling engine, mounted within a cradle, and a lift winch are attached to the support tower. A stabilizer bar is attached to the lower end of the support tower to prevent swaying of the support tower. The engine transfers torque to the transmission mounted below the engine, to which a steel swivel, housing a quill, allows passage of air and/or water to a drill steel to provide rotary force to power a drill bit. A pull-down system, preferably a weighted bar, is attached to the lower end of the support tower and to the drilling engine to pull the drilling ending downwardly. Manual transport is provided by means of a main base wheel dolly system for easy one-man mobilization. A counterweight is attached to the lower end of the support tower to prevent the support tower from being lifted as the pull-down system forces the drilling bit into the ground.