The invention discloses a quick earth auger for cable construction. The quick earth auger comprises chassis connecting rods arranged symmetrically front and back, and a device box body is fixedly installed on the chassis connecting rods; the device box body is internally provided with a first gear cavity, and a gear shaft is internally provided with a drilling shaft through a spline; the bottom ofthe drilling shaft is provided with a drill bit for drilling; and a drilling motor is started, and a gear is driven by the drilling motor to rotate, and the gear shaft is rotated for driving the drilling shaft and the drill bit to rotate for drilling a hole in soil. According to the quick earth auger, a cable pit required for cables can be dug quickly, and a drilling piece can be regulated into an oblique state; a small pit formed properly is expanded, and repeated drilling operations are not required; the drilling shaft is portable, and soil upon completion of drilling can be dug up in one time, and is not piled together all the time, so that the cable construction is facilitated.