Abstract: A scale removing apparatus 7 in accordance with the present invention subjects the internal surface of the steel pipe 3 to a blasting process wherein abrasive particles (not shown) are ejected through a high-pressure jet nozzle 2 and collide with the internal surface of the steel pipe 3. The scale removing apparatus 7 has the high-pressure jet nozzle 2 for ejecting the abrasive particle, a dust collector 4 for collecting dust particles after blasting, and restraining means 6 for restraining air from flowing into the steel pipe 3 from an end part of the steel pipe 3 along with the transfer of abrasive particle ejected through the high-pressure jet nozzle 2. Therefore, the scale can be removed without scattering of dust particles into the atmosphere even with a low-capacity dust collector.