An ultrasonic device has ultrasonic elements to transmit and receive ultrasonic waves. The ultrasonic device includes a first ultrasonic element array in which ultrasonic elements forming one channel among the ultrasonic elements are arranged in a first direction (scan direction) and a second ultrasonic element array in which ultrasonic elements forming one channel are arranged in the first direction. The second ultrasonic element array is disposed so as to be shifted from the first ultrasonic element array in a second direction (slice direction) crossing the first direction.
