PROBLEM TO BE SOLVED: To accurately locate a detection object within a subject when detecting the detection object using an ultrasound probe.SOLUTION: An ultrasound diagnostic apparatus 1 receives a reflection-related reception signal from an ultrasound probe 2, the ultrasound probe including: a plurality of transducers 210 disposed in a first direction and configured to transmit an ultrasound beam to a subject and receive reflection thereof； and a transducer switching unit 24 for controlling a drive signal to the plurality of transducers 210 to deflect a transmission direction of the ultrasound beam to the first direction. The ultrasound diagnostic apparatus comprises: a locating unit 11b for determining a depth of a detection object within the subject, based on temporal changes of the reception signal； and another locating unit 11b for locating the detection object in the first direction, based on the reception signal generated by the reflection from the detection object when the transmission direction of the ultrasound beam is changed between different first and second angles.SELECTED DRAWING: Figure 2【課題】超音波探触子を用いて被検体の内部の検出対象物を検出する際に、当該検出対象物の位置を正確に特定すること。【解決手段】第１の方向に沿って配設され、被検体に対して超音波ビームを送信してその反射波を受信する複数の振動子２１０と、複数の振動子２１０への駆動信号を制御して、超音波ビームの送信方向を第１の方向に偏向させる振動子切替部２４と、を有する超音波探触子２から反射波に係る受信信号を受信する超音波診断装置１であって、受信信号の時間的変化に基づいて、被検体の内部における検出対象物の深度を特定する位置特定部１１ｂと、超音波ビームの送信方向が異なる第１及び第２の角度のときに検出対象物からの反射波により生成された前受信信号に基づいて、第１の方向における検出対象物の位置を特定する位置特定部１１ｂと、を備える。【選択図】図２
