A capacitive micromachined ultrasonic transducer includes a device substrate including a first trench confining a plurality of first parts corresponding to a plurality of elements and a second trench confining a second part separated from the plurality of first parts, a supporting unit provided on the device substrate for confining a plurality of cavities corresponding to each of the plurality of elements, a membrane provided on the supporting unit to cover the plurality of cavities, an upper electrode provided on the membrane and electrically connected to the second part in the second trench through a via hole passing through the membrane and the supporting unit, and a through-silicon via (TSV) substrate provided on a lower surface of the device substrate, and including a plurality of first via metals connected to the plurality of first parts and a second via metal connected to the second part.