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The fluidized bed process was originally used for the drying of pharmaceutical granulations.However,over the years,coating process has introduced.Fluidized bed coating process has numerous advantages such as the ability to handle a wide range of particles sizes and shapes;furthermore it can produce highly uniform coating.The main purpose of this study was to design fluidized bed coating process with an atomization nozzle assembly and investigate the factors influencing the quality of coating.This investigation confirms that a uniform coating with desired thickness can be achieved through the manipulation of key variables of liquid properties,atomization process and fluidized bed parameters.The fluidized bed chamber and atomization assembly were determined as the most important equipment in the fluidized coating process.The coating liquid,which was gelatin aqueous solution,was investigated.The coating liquid viscosity with different concentrations and their gel temperature has been studied to determine the concentration can be used in the coating process.Spray droplets size was determined to be an important factor in coating process.The experiments revealed that droplets size increase with the increase of spray coating viscosity and the increase of spray liquid flow rate,it decrease with the increase of atomization firflow rate and air pressure.For coating uniformity and thickness range,the air fluidization particles weight and fluidization temperature were found to be influencing factors.