The invention relates to a high-power radial vibration piezoelectric ultrasonic transducer suitable for liquid ultrasonic treatment under normal pressure and high pressure. The purpose of the present invention is to provide a high structural strength, high power density, which can generate uniform sound radiation in the radial direction of 360°, aiming at the defects of low structural strength and low power density of existing ultrasonic transducers, It is a high-power radial vibration piezoelectric ultrasonic transducer especially suitable for liquid ultrasonic treatment under normal pressure and high pressure. The invention comprises a piezoelectric ceramic disc, a prestressed annular cover plate, a cylinder body, an insulating vibration-isolating ring pad and an end cover, wherein a through hole is arranged on the piezoelectric ceramic disc, and the side of the piezoelectric ceramic disc and the prestressed annular cover plate The composite disk piezoelectric transducer is formed by radial compounding. Several composite disk piezoelectric transducer units whose geometric parameters are consistent with the radial resonance frequency are connected in electrical parallel, and are closely fixed on the inner wall of the cylinder at equal intervals. An insulating vibration-isolating ring pad is arranged between two adjacent composite disc piezoelectric transducer units.