In a surface acoustic wave device, an excitation electrode 5 in a surface acoustic wave element is provided on a lower surface of a piezoelectric substrate 3, and the lower surface of the piezoelectric substrate 3 is disposed in a state where it is opposed to an upper surface of a mounting base member 2. The surface acoustic wave device comprises a through hole 9 penetrating between the upper surface and a lower surface of the mounting base member 2, a lead electrode 10 closing the through hole 9 and formed so as to extend to the lower surface of the mounting base member 2, and an insulator 11 covering the lead electrode 10 so as to expose its partial area 16. When the surface acoustic wave device is mounted on a circuit board or the like, therefore, the through hole 9 is closed by the insulator 11, so that no bubbles are produced in the through hole 9, and cracks can be prevented from appearing, thereby making it possible to provide a highly reliable surface acoustic wave device having no inferior connection or the like.

 
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