Using renewable energy sources to replace fossil energy sources is one of the best solutions to solve energy shortages, environmental pollution and minimizing the impact of the greenhouse effect. The high potential biomass energy source in Vietnam is an one needs to be exploited and applied, in which biomass gasification methods to supply gas for industry and life needs to be studied and developed. However, the gas product obtained from biomass gasification (raw gas) contains many impurities such as tar, alkali metal, HCl, nitrogen and HCN, H2S and COS.... Therefore, the raw gas requires to be cleaned and cooled before they might be used by using suitable technology and equipment. Two approaches of raw gas cooling and cleaning are venturi tube device and cyclolone filter device combined with forced circulation convection cooling have been developed, manufactured, and tested successfully. The results indicate that the cyclolone filter device combined with forced circulation convection cooling has many advantages and cools the gas temperature below 500C before it might be used for storage step.