Ultrasonic probe includes ultrasonic wave transmitting and receiving unit (20) and provides in shell (30,50) And driving device, it is provided with and contains a main sound bearing medium and swing ultrasonic wave transmitting and receiving unit (20). Ultrasonic probe is characterized in: the driving of the driving device is the ultrasonic wave transmitting and receiving unit (20) that a kind of rotation of mechanism driving-motor is converted into and swings (1) All or part of drive transmission mechanisms includes gear mechanism Prevent at least a pair of of gear (8,9) of sideshake engaging portion in gear mechanism, flowing to another gear mesh (8) by being resiliently urged to and pressed a gear mesh (9) passes through compressed spring (11,102).
