An investigation was carried out to study the production and optimal activity of exo- xylanase by Solid state fermentation using sugar cane bagasse as the agricultural residue. A total of 31 molds were isolated and thereafter screened for their ability to produce xylanase by using the plate assay technique on potato dextrose agar fortified with 2% (w/v) of xylan. Promising mold isolates for xylanase production were identified as XA, XC3, XD2, XM6 (Aspergillus niger), XC (Tricoderma harzianum), XC1 (Fusarium oxysporum), XC2, XM2 (Aspergillus terreus), XD3, XJ, XK (Aspergillus fumigatus), XM (Aspergillus tamarii). Studies on the optimal conditions of performance of temperature and pH of the produced xylanase were in a range of 300C - 800C and 3.0 - 9.0 respectively. Comparative Studies of the enzyme for its activity as produced by isolate XM, XD and XC were 3000U/ml, 2800U/ml and 3400U/ml respectively. While the specific activity were 246.5U/mg/ml, 97.15U/mg/ml and 123.63U/mg/ml respectively.