An ultrasonic device includes: a substrate on which ultrasonic elements configured to transmit and receive ultrasound and a cable electrically connected to the ultrasonic elements are installed； an acoustic lens having a plurality of projecting portions connected to one of the substrate and the cable； and an acoustic matching unit located between the substrate and the acoustic lens, wherein the projecting portions extend along an outer perimeter of the substrate, and the projecting portions are provided at a lower ratio per unit length in a direction in which the projecting portions extend in a place where the cable is installed than in a place where the cable is not installed.
