In the dry cement production technology, fuel combustion and raw material decomposition in the calciner have important effectson cement quality and pollutant emission. Compared with the combustion of fuel directly injected into the calciner, the combustion performance of the fuel in the calciner can be improved and the emission of harmful gases can be reduced by the preheating treatment, andthe fuel adaptability of the cement calciner can be increased. The preheating characteristics of coal and biomass mixed fuel preheatedby circulating fluidized bed before entering the calciner was studied, that was, the influence of different factors on solid preheated fueland gas. The results show that the increase of oxygen-carbon ratio (molar mass ratio of O2 to C per unit time) will lead to more intense reaction and particle collision in preheating furnace, resulting in a decrease in the particle size of preheated fuel. At the same time, theash content of coke produced by coupling preheating of coal and rice husk increases and other components decrease with the increase of oxygen-carbon ratio. The heating of external heat source can significantly increase the generation of effective combustion components of gassuch as CO, CH4 and H2, and improve the conversion rate of each component in solid phase fuel.