Bacillus subtilis DJ5 was found to produce hyperthermostable beta amylase in a complex medium during submerged fermentation. The media was optimized for improved production of hyperthermostable β amylase following one variable at a time (OVAT) method. Initial medium pH of 7 and cultivation temperature of 37 °C were optimal for enzyme production. Among different nitrogen and carbon sources tested, 0.05% tryptone and 5% starch were most effective for enzyme yield. Little supplementation of lysine (0.03%) remarkably increased enzyme titer (14.24 U/ml). Nitrate (0.03%) played a major role in microbial growth and subsequent enzyme production. Enzyme production was increased upto 1.67 fold in optimized medium. Optimized media resulted in higher enzyme titer (18.32 U/mg) than basal media (10.97U/mg).