Abstract: The present study is concerned with the optimization of cultural conditions for maximum conversion of L-Tyrosine to L-DOPA by strain of Aspergillus oryzae ISB-9. The effect of time course, temperature and pH on the production of L-DOPA was checked. Surface culture method was employed for L-DOPA fermentation. Optimum temperature and time for L-DOPA production is 50 C and 60 minutes respectively. However, the optimum pH of mycelium development was 5.0 because maximum production of L-DOPA (0.95 mg ml-1) was observed at this pH. The acidic pH (3.0) of reaction mixture was found to be optimum for higher L-DOPA production (1.1mg ml-1).