Abstract: The pressure fluctuation time series of gas-solid fluidized beds contains abundant information of dynamic characteristics. However, there is no accurate and reliable method to extract the embedded information due to the highly random nature of fluidization. In this work,by adopting the concept of mutual information in Shannon information theory, the authors investigate the dependence between pressure fluctuation time series in the reconstruction phase space at two different locations in the fluidized bed. The curve of mutual information indicates that there exists high-speed information transport in the fluidized bed. The average information transport speed of pressure fluctuation and its changes with gas velocity is detected by experiments. The authors argue that the information is transferred with the disturbing of particles in the beds, and the information transport speed decreases with the increasing of interspace rate.