Transmitting and receiving the signal line for transmitting a received ultrasonic signal to and from a plurality of ultrasonic transducers, which is provided in the vicinity of a plurality of ultrasonic transducers, ultrasonic diagnostic apparatus, synchronized with the transmission signal to form a received signal and determines the read signal for reading the selection signal or a selection signal for selecting the ultrasonic transducer to be driven to be delivered by, and electrically connected to the reception signal line ultrasonic transducers to be driven by the determination result and a signal determination unit, transmitting and receiving the signal line for transmitting a read signal or the selection signal and also serves as the transmission and reception signals.超音波診断装置は、複数の超音波振動子との間で超音波の送受信信号を伝送する送受信信号線と、複数の超音波振動子の近傍に設けられ、送受信信号を形成する送信信号に同期して送出される駆動対象の超音波振動子を選択するための選択信号又は選択信号を読み出す読出信号を判別し、判別結果により駆動対象の超音波振動子を送受信信号線に電気的に接続する信号判別部と、を備え、送受信信号線は送受信信号と兼用して選択信号又は読出信号を伝送する。
