The ultrasonic wireless power transmission technology is researching as the one option of wireless power transmission technologies, because the loss of the electromagnetic wave becomes larger around a human body area or under juicy environments. For highly efficient power transmission, it is necessary to investigate the transducer as the transmitter and the receiver. In this paper, the frequency characteristic of transmission efficiency depended on matching condition of developed transducer is investigated. As results, the transmission efficiency is made wideband to select optimal matching condition at each frequency. Especially, maximum transmission efficiency is 75.1% at designed frequency 1.20MHz.