Fouling is inevitable in fluid-conveying pipes which can decrease flow rate, reduce thermal conductivity and increase energy consumption significantly, even cause industrial accidents. As there are some drawbacks in existing descaling methods, a new approach based on leaky guided ultrasonic waves cavitation is proposed in this paper, which is non-destructive and able to cut down downtime costs compared to the existing methods. This paper includes theoretical studies, finite element modeling work and a series of experiments. A frequency selection principle has been proposed to assure that the descaling process is non-destructive and uniform. The results show that this new approach is of high efficiency in descaling a water-filled pipe. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.