The biological generation of silver nanoparticles (AgNP) is a straight forward process. However, the mechanism by which this process takes place is unclear. We demonstrate the synthesis of AgNPs using fungal filtrate of Aspergillus oryzae. A characteristic peak of AgNP formation was detected at 435 nm. Eight most prominent extracellular protein bands were identified using MALDI/TOF Mass spectrometry. Here, we suggest that proteinaceous molecules such as some amino acids, play an essential role in converting AgNO3 into AgNP. Moreover, this is the first report suggesting that AgNP are stabilized by the chelating agent, 5-hydroxy-2-hydroxymethyl-1,4-pyrone (kojic acid). Our findings suggest that this species would be useful for large scale AgNP production. Keywords: Aspergillus oryzae, MALDI-TOF, Silver nanoparticles