PROBLEM TO BE SOLVED: To accurately recognize the scan center position of an ultrasound probe when paracentesis is performed using the ultrasound probe.SOLUTION: An ultrasound probe according to the present invention includes, on a surface of a casing, a center position indication part for indicating an approximate center position of at least one surface of an ultrasound send/receive side surface of a piezoelectric element. The center position indication part is defined such that tangents intersect each other at each of a first intersection and a second intersection located on a virtual centerline passing through the center position in the ultrasound send/receive direction and that the tangents intersecting each other have gradients of opposite signs. The first intersection is located on the ultrasound send/receive side of the piezoelectric element, and the second intersection is located on a side opposite to the ultrasound send/receive side of the piezoelectric element relative to the first intersection. The tangents intersecting at the first intersection form a portion protruding toward the ultrasound send/receive side of the piezoelectric element, and the tangents intersecting at the second intersection form a portion protruding toward the ultrasound send/receive side of the piezoelectric element or a portion recessing away from the same side.SELECTED DRAWING: Figure 3【課題】超音波探触子を用いて穿刺術を行う際に、超音波探触子の走査中央位置を正確に認識する。【解決手段】本発明の超音波探触子は、筐体の表面に、圧電素子の超音波送受信側の面の少なくとも一辺の略中央位置を指示する中央指示部を有し、中央指示部は、前記略中央位置を通過する超音波送受信方向の仮想の中央線上に位置する第１、第２との２つの交点それぞれにおいて、接線が互いに交差し、且つ、互いに交差する前記接線の傾きが異符号であるように構成されており、第１交点は圧電素子の超音波送受信側に位置し、第２交点は、第１交点よりも、圧電素子の超音波送受信側とは反対する側に位置し、第１交点で交差する接線は、圧電素子の超音波送受信側に向いて凸部を形成しており、第２交点で交差する接線は、圧電素子の超音波送受信側に向いて凸部又は凹部を形成している。【選択図】図３
