Fluid-solid fluidized bed reactors may be classified by various types according to kinds of contacting of solids by fluid, operating conditions, the dynamic behaviour of the solids, or the mode of solid movement（circulation）. The fluid-solid fluidized system which belong to the first(kinds of contacting of solids by fluid) divide into two categories, so-called "an aggregative fluidized bed, or a bubbling fluidized bed" and " a particulate fluidized bed, or a homogeneously fluidized bed". The former is industrial importance for many gas-solid reactions. Many two-phase reactor models have been proposed in an effort to predict chemical conversions in aggregative fluidized beds(or gas-fluidized beds). In this paper the assumptions underlying these models are considered, and it is showen their characteristics of some models. In recent years a considerable amount of work has been carried out on electrodepositions, batteries and preparations of chemicals using electrochemical fluidized bed reactors(fluidized bed electrode), one of particulate fluidized beds. It is consists of a bed of conducting particles fluidized by the upward flow of electrolyte through some form of distributor and all bed-particles act as an electrode. The basic principles of the fluidized bed electrode and their characteristics are also reviewed here.