Problem to be solved: to suppress the attenuation of the signal in the acoustic coupler while ensuring the BIOCONTACT of the acoustic coupler.Solution: the ultrasonic probe according to the embodiment comprises a vibrator group having a plurality of ultrasonic oscillators and a transmitting / receiving side of the vibrator group, and at least the body contacting member having a convex contact body contact surface in the region corresponding to the acoustic effective aperture of the vibrator group.In the BIOCONTACT surface of the bio contact member, the radius of curvature at the intersection of a plurality of virtual surfaces and a biomechanical contact plane parallel to the transmitting and receiving main axes of the vibrator group and the virtual plane parallel to the transmitting and receiving main axis, and the virtual radius parallel to the transmitting / receiving main axis, monotonously increases as the intersecting line approaches the outer edge of the BIOCONTACT surface It has a shape.Diagram【課題】音響カプラの生体接触性を確保しつつ音響カプラにおける信号の減衰を抑制すること。【解決手段】実施形態に係る超音波プローブは、複数の超音波振動子を有する振動子群と、振動子群の送受信側に設けられ、少なくとも振動子群の音響的有効口径に対応する領域に凸形状の生体接触面を有する生体接触部材と、を備える。生体接触部材の生体接触面は、振動子群の送受信主軸に平行な複数の仮想面と生体接触面とのそれぞれの交線の、前記複数の仮想面に交わり且つ送受信主軸に平行な仮想面との交点における曲率半径が、交線が生体接触面の外縁に近づくほど単調に増加する形状を有する。【選択図】 図６
