An ultrasonographic technique capable of forming a transmission beam enabling multi-beam transmission/reception of identical transmission sensitivity. An ultrasonographic device for imaging inside of an examinee includes a transmitter for transmitting an ultrasonic pulse signal from an ultrasonic element array to the examinee, and a receiver for receiving the ultrasonic pulse reflected from the examinee. The transmitter transmits an ultrasonic pulse signal having a plurality of peaks of substantially equal transmission intensity in the azimuth direction and a trace in the depth direction of each peak as a substantially straight line, from a transmission opening of the ultrasonic element array to the examinee.