Silver nanoparticle is a nontoxic, safe inorganic antimicrobial agent and is capable of killing about 650 type of microorganisms. In this study, the results showed that the effectiveness of silver nanoparticles (AgNPs) inhibition the fungus Aspergillus flavus. The maximum inhibition of the fungus growth on the PDA 100% for concentration of 200 ppm, 175 ppm while 95% inhibition of 150 ppm. Silver nanoparticles also prevented the production of AFB1 in stored maize grain using HPLC showed 100% inhibition ratio the growth of fungus in maize sample contaminated with the fungus.