Abstract: Time course of xylanase' production was studied by culturing Strepotmyces albus in different substrates for 240 h. The results show that xylanase demonstrates different activities in different substrates. For induction of xylanase, wood powder is better than xylan, while a compound substrate is better than a single one. After Strepotmyces albus is cultured for 144 h in the optimal enzyme-induction medium, the production of xylanase culminates, with a maximum enzyme activity of 45.66 U/mL. The results show that the xylanase from Strepotmyces albus has the characteristics of both thermotolerance and alkali-tolerance, showing that 83.46% of its maximal activity remains after a treatment for 30 min at 90℃, and the highest activity in pH 7.0.