Abstract: Pipe cleaning apparatus is provided, including a compressed air supply unit, a liquid supply unit, and a control unit. The compressed air supply unit generates compressed air and supplies a target pipe to be cleaned with the generated compressed air. The liquid supply unit pumps a liquid and supplies the target pipe with the pumped liquid. The control unit controls the compressed air supply unit and the liquid supply unit to be alternately supplied with the compressed air and the pumped liquid at a predetermined interval. According to the pipe cleaning apparatus, since the target pipe is alternately supplied with the compressed air and the pumped liquid which have different compression and expansion ratios, the compressed air and the pumped liquid simultaneously undergo compression and expansion to then move forward. In addition, a force of oscillatory movement applied to sludge or scale deposited on the interior surface of the pipe and a movement rate are increased.