An ultrasonic sensor has two or more ultrasonic arrays disposed on a probe surface, and a delay control unit that controls a transmission angle of ultrasonic waves transmitted from the ultrasonic arrays. The ultrasonic arrays have a linear array structure in which a plurality of ultrasonic elements are arranged in a linear scanning direction, and the delay control unit controls the timing for transmitting ultrasonic waves from the ultrasonic elements and controls the transmission angle of the ultrasonic waves transmitted from the ultrasonic arrays. Two of the ultrasonic arrays have linear scanning directions that are different from each other and are arranged in positions that are spaced apart from each other.