The effect of fermentation of peanut milk with lactic acid bacteria on n-hexanal content was investigated. Changes in pH, titratable acidity and viable cell populations indicated that Streptococcus salivarius subsp. thermophilus was adapted better than Lactobacillus delbrueckii subsp. bulgaricus during fermentation. Analysis of headspace volatiles revealed that n-hexanal, which is one of the compounds responsible for undesirable green/beany flavor in peanut milk, completely disappeared as a result of fermentation. S. salivarius subsp. thermophilus was more effective than L. delbrueckii subsp,. bulgaricus in reducing the n-hexanal content. No significant difference was found in water sorption between fermented and unfermented peanut milk.