Abstract: Rice husk, millet straw, guinea corn stalk and sawdust were used as fermentation feed substrate for the evaluation of cellulase activity secreted by Aspergillus candidus. The substrates were pretreated with 5% NaOH (alkaline treatment) and autoclaved . From the fermentation studies, rice husk, millet straw and guinea corn stalk feed substrates showed the highest cellulase activity of 7.50, 6.88 and 5.84 IU, respectively. The effect of pH showed that optimal pH for maximum cellulase activity varied in each of the substrates used. Rice husk and millet straw had maximum enzyme activity at pH 5, while guinea corn stalk and sawdust had maximum activity at pH 3 and 4, respectively. From this study, Aspergillus candidus holds the potential of converting lignocellulose materials into products of commercial and industrial values such as glucose and other biofuels.