Abstract: The vibration transmission properties of joint beams were investigated by measurement. It was found that the frequency at which the peak of vibration transmission loss appears corresponds to the resonance of the cantilever (the part between the bolt and the edge of the beam at the joint) and is in agreement with the intrinsic frequency of the beam. The vibration transmission loss as high as 30 dB can be achieved at expectant frequency if proper parameters of the cantilever were selected. The conclusion, in practice, might have an important application.