An ultrasonic transducer having a flexible printed circuit board with a thick metal layer and a manufacturing method thereof are disclosed. The ultrasonic transducer, according to an embodiment of the present invention, comprises: an active element that generates an ultrasonic signal, wherein the active element has a thickness of ¼λ or less at the center frequency of the generated ultrasonic signal； and a flexible printed circuit board that includes a metal layer with a predetermined thickness, which is formed on one surface of the active element and is electrically connected to the active element, wherein the metal layer blocks ultrasonic waves that propagate in an opposite direction to a predetermined travel path of the ultrasonic waves.
