An ultrasonic probe includes a first coupled vibration member and a second coupled vibration member each of which extends along a longitudinal axis between a first anti-node position of an ultrasonic vibration and a second anti-node position of the ultrasonic vibration located to a distal direction side of the first anti-node position. The second coupled vibration member vibrates in the same mode as the first coupled vibration member. A first groove of the first coupled vibration member and a second groove of the second coupled vibration member cooperate with each other and thereby form at least a part of a passage inside a multiple-members vibrating portion formed by the first coupled vibration member and the second coupled vibration member.
