Abstract: [Objective] We cloned xylanase-encoding gene xynA and its promoter from Bacillus pumilus, expressed in Bacillus megaterium and characterized the recombinant xylanase. [Methods] We inserted the xylanase-encoding gene xynA and its promoter in Bacillus expression vector pWH1520 and pWG03 which was modified from pWH1520. We transformed the recombinant plasmid pWTEJX and pWGXYN into Bacillus megaterium, and obtained the recombinant stains BMJXH9 and BMGpp12. Enzymes produced by recombinant strains expressing xynA were produced in the medium. The xylanase activity produced by recombinant BMGpp12 was three times higher than that of BMJXH9. The recombinant xylanase had the original enzyme alkali-tolerant properties. [Conclusion] Alkali-tolerant xylanase gene was successfully expressed and this provided a basis for further study of xylanase applied.