<P>In order to improve the cellulase-producing ability, the culture medium components and condition were optimized. The results showed that the cellulase activity in the fermentation broth remarkably increased by using 1% corncob residue combined with 1% wheat bran and 1% corncob as carbon source, taking 0.75% soybean meal and 0.3% KON3 as nitrogen source, and adding 0.3% CaCO3 to stabilize the pH to 5.0. The FPase activity in supernatant of A. niger FC-1 fermented with 50mL of the optimal medium in 250mL shake flasks at 30°C reached 101.6U/mL, which was 4.7 times of that before optimization.</P>