The invention relates to an ultrasonic transducer which is used in sonic wave testing of rock, rock mass and concrete structures as well as underwater monitoring, in particular to an ultrasonic radial transducer which can eliminate interference signals and realize accurate measurement with high SNR (signal to noise ratio). The invention is mainly characterized in that the side face of a cylinder on a non-effective transmitting and receiving part of the transducer is provided with a layer of fine and soft plush bodies. By using the flexible supporting, positioning, shaking reduction, anticollision and noise elimination functions of the plush body, the invention can fundamentally fulfill the aims of interference-free transmitting and high-fidelity receiving, make the detection signal more stable and reliable, and ensure that the host can accurately carry out automatic detection and evaluation, thereby achieving the effect of obviously improving the work efficiency and ensuring the construction quality.