In the CFD simulation of industrial-scale bubbling fluidized beds, coarse grids are necessary due to limited computation resources, which creates a problem about how to characterize the effect of meso-scale bubbling structures on the particulate phase stresses and inter-phase interaction force. In this paper, the two-phase theory of bubbling fluidization is applied in the analysis of the fluctuation characteristics of solid volume fractions and then it was used to establish a simple model for granular temperature in bubbling fluidized beds, which is based on the local pseudo-thermal energy balance. It was shown that the granular temperature obtained experimentally is well predicted by the present model.