On examination was performed for the optimization of xylanase production by Neosartroya tatenoi KKU-CLB-3-2-4-1 was carried out using central composite design (CCD) and response surface methodology (RSM) of experiments inorder to study the influence of process variables (Initial pH, Introgen concentration and Initial moisture) on enzyme production. The analysis of variance indicated that the established model was significant (P< 0.05) an the lack of fit was not significant trust values 95% with R2 equal to 0.95. Be valuable F Value and Prob > F at 6.75 and 0.0031, respective. Under the optimized condition for xylanase production by response surface analysis were initial pH 8.77, introgen concentration 0.93% and initial moisture 80% , respective. which the predicted xylanase production value of 7.33 U/g dry weight and validation experiments of xylanase production at 7.49 U / g dry weight which higher than predicted at 2.19%. The maximum xylanase production was observed at 6 day of cultivation.