The invention discloses a gene engineering strain for recombinant expression of Bacillus stearothermophilus alpha/beta-CGT enzyme and application of the gene engineering strain, belonging to the fields of gene engineering and enzyme engineering. According to the invention, the recombinant plasmid p SVEB-alpha/beta-CGTase is constructed, and Bacillus pumilus Brevibacillus brevis (CCTCC AB 94025) is transformed, so that recombinant Bacillus pumilus is obtained; based on the recombinant Bacillus pumilus as the strain, fermentation is carried to produce an alpha/beta-CGT enzyme which is applied to preparation of beta-cylodextrin and has good effect. The gene engineering strain for recombinant expression of Bacillus stearothermophilus alpha/beta-CGT enzyme disclosed by the invention has the advantages that the food-safe Bacillus pumilus is adopted as an expression host to recombine and produce alpha/beta-CGT enzyme, the recombinant strain is high in enzyme production, the ferment materials are wide in resources, and the production cost is relatively low.