PURPOSE: To form a piezoelectric body for ultrasonic delay lines without characteristic degradation due to resonance by adhering an input part and an output part together with an oscillation absorber between, and forming them into one body.

CONSTITUTION: A piezoelectric body base material is formed by pasting two piezoelectric bodies 1a and 1b by resin layers with an oscillation absorber 2 made of material through which it is hard to propagate oscillation. Plate piezoelectric bodies 1a and 1b are adhered on the input/output face of a glass medium 3 through which ultrasonic waves are propagated with an electrode film and a resin layer between. Since the piezoelectric bodies 1a and 1b respectively in charge of input and output are formed into one plate like this, it can be efficiently and easily adhered on the small input/output face of the glass medium 3, and since it is adhered with the oscillation absorber 2 through which it is hard to propagate the oscillation between, the resonance can be prevented and the piezoelectric body for the ultrasonic delay lines whose characteristic is not be degraded can be obtained.