The invention provides a portable lifting device for building construction. The device is characterized by comprising a transverse supporting rod, an oblique tensioning traction rod, a lifting steel wire rope, a lifting hook, a fixed pulley, a motor and a length adjusting rod, wherein the transverse supporting rod is fixedly mounted on a vertical column; the oblique tensioning traction rod is mounted at the upper end of the transverse supporting rod; the lifting steel wire rope is connected with the lifting hook, and the lifting steel wire rope and the lifting hook are both mounted at the upper end of the transverse supporting rod; the lifting hook is mounted at the upper end of the lifting hook; the fixed pulley is mounted on the side surface of the upper end of the lifting hook; the left end of a telescopic adjusting device is mounted on the side surface of the upper end of the lifting hook by a hinging manner; the motor is mounted at the upper end of the bracket; an electric machine is mounted in the vertical column; one end of the steel wire rope coils an output shaft of the motor and sequentially bypasses the fixed pulley and the motor; hoisting hooks are sequentially arranged at the other end of the steel wire rope. The device has the advantages of being simple in principle and structure, low in fault rate, stable in performance, and wide in applicable scope.