Xylanase play important role in many industries because reduce using of chemicals and reduce the environment pollution, that caused by chemical compounds. Xylanase in this study produced by Bacillus tequilensis strain, which chosen from forty bacterial isolates isolated from Ain-Helwan spring water (hot) and soil. The Bacillus tequilensis strain was the most potent isolate that give large amount of xylanase so subjected to identification by 16s rRNA sequence analysis and more studies for detection of the optimum factors that make it give the highest xylanase production. To improve the production of xylanase, the optimum factors subjected to studying with Box-Behnken design resulted in the xylanase activity becoming (51.51 U/mL). The Bacillus tequilensis xylanase extracted from broth culture by precipitation with ammonium sulphate (60 %), then the enzyme enhanced with dialysis and purified with sephadex G-100 column chromatography. Purified xylanases had a 12-fold enrichment, with a specific activity of 76.83 U/mg and a molecular weight approximately 359.0 KDa. The amino acids content of xylanase obtained from Bacillus tequilensis were 16 amino acids, started with aspartic acid and finished with proline, from these amino acids found two amino acids with highest concentration arginine 1410 mg/L and glycine 900 mg/L. Xylanase produced by B. tequilensis strain used in biobleaching, where it gives the highest brightness (61.4 %), in case the control sample was (48 %), with increasing 13.4 % about the control sample. This xylanase used to bioleaching the waste paper as alternative of chemical compounds that used in the bleaching process.