The microbial utilization of fish silage as a fermentation substrate for the extracellular production of L-lysine by Corynebacterium glutamicum ATCC 21543 was studied in Erlenmeyer baffled flasks. When culture media were supplemented with fish silage at 40 g/l the concentrations of biomass and L-lysine attained 10 and 30 g/l, respectively after 72 h of fermentation. Kinetic fermentation data. the specific rate of L-lysine production and the product yield reached maximum values of 0.096 g/g h and 0.30 g/g, respectively, when yeast extract was replaced by fish silage in culture media. Statistical analysis showed that there was not a significant difference (P > 0.05) between yeast extract (20 g/l) and fish silage (40 g/l) kinetic fermentation data.