An ultrasonic device includes an element substrate provided with an ultrasonic transducer array in which a plurality of ultrasonic transducers are arranged in an array, a sealing plate (array counter plate) that is bonded to the element substrate and covers at least the ultrasonic transducer array, and a support substrate that supports at least one of the element substrate and the sealing plate, and the support substrate has a through hole (insertion section) into which at least part of the sealing plate is inserted.
