Sodium bicarbonate, commercially available dry chemical powder was tested for the extinguishment of sodium fire. Sodium fire tests were performed on various scale to observe the powder extinguishant, sodium bicarbonate. It was found that sodium bicarbonate was more effective than any other extinguishants. As a result of experimental observation, the powder floated on top of sodium pool and covered effectively the surface of burning pool. None of substantial reaction was observed at the interface. And only small quantity of powder was required. Effect of particle size on extinguishment was found very great. The particle size range was very effective range up to approximately 40 μm and relatively ineffective range above 50 μm for the extinguishment of sodium fire.