Abstract: The bubble velocity in dense bubbling zone of the fixed valve tray plate was measured by the double-sensor conductivity probe. The fractal characteristics and distribution of bubble velocity in different vertical heights, as well as the behavior of bubble movement in different foam zones, were also investigated. The results showed that the distribution of bubble movement in different vertical heights along the same direction was similar. The change of bubble velocity showed a weak double peak shape, and was not fluctuant near the tower center. The bubble velocity distribution on the tray plate was of fractal characteristics with a fractal dimension ranged from 1.04 to 1.25, which reduced at first, and then increased along the vertical height. In the deep foam zone, the turbulent intensity of the bubble motion could be characterized very well by the fractal dimension of bubble velocity distribution, which showed the linear relation between them. There existed an exponential function relationship between turbulent intensity, fractal dimension of bubble flow and the height of foam.