An ultrasonic transducer comprising piezoelectric resonators, a matching layer formed on the ultrasonic oscillation surfaces of the resonators, and a backing material adhered on the opposite surface to the ultrasonic oscillation surface, wherein a cylindrical case is fixed to the circumference of the resonators and the backing material is formed by being cast into the case. A method for manufacturing the ultrasonic transducer, wherein the piezoelectric ceramic is temporarily fixed on a metal support and divided into a predetermined shape and a backing material is formed as such that lead wires are allowed to extend through the backing material.