An ultrasonic probe includes a probe main body section； and a curved extending section which is provided on the distal side with respect to the probe main body section, and which is extended in a state of curving relative to the probe main body section toward a first intersecting direction side in a case where a certain direction intersecting the longitudinal axis is defined as the first intersecting direction. The curved extending section includes a first curved outer surface facing the first intersecting direction side, and a second curved outer surface facing a second intersecting direction side that is a side opposite to the first intersecting direction. A first curve start position at which the first curved outer surface starts curving relative to the longitudinal axis toward the first intersecting direction side is positioned on the distal side with respect to a second curve start position at which the second curved outer surface starts curving relative to the longitudinal axis toward the first intersecting direction side.
