The invention relates to petroleum pipe inner wall rust removing equipment capable of automatically scraping impurities. The equipment comprises a rust removing support block; the right end surface of the rust removing support block is welded with a transmission support shaft; a transmission ring 1 is mounted on the outer wall of the middle part of the transmission support shaft through two transmission bearings 1; an annular rack is welded on the outer wall of the transmission ring 1, and is uniformly engaged with four transmission mechanisms in the axis direction; the bottom ends of the four transmission mechanisms are uniformly welded on the side wall of the transmission support shaft; the transmission mechanisms include transmission support blocks welded on the outer wall of the transmission support shaft; transmission motors are mounted on the side walls of the transmission support blocks; the transmission support blocks achieve an effect of supporting the transmission motors; transmission gears are mounted on output shafts of the transmission motors, and are engaged with the annular rack; four connecting shafts are uniformly welded on the right side of the transmission ring 1; and transmission rings 2 are welded at the right end of the four connecting shafts. The equipment can realize quick impurity scraping, rust removing and polishing functions for an inner wall of a petroleum pipe.