The ADTZ gene primers were synthesized through the ADTZ gene sequence published by GenBank. The ADTZ gene fragment was screened by PCR from the mixed bacterial solution which extracted of the moldy corn sample, and transformed into E. coli by constructing expression vector. The size and concentration of the ADTZ expression product were detected by SDS-PAGE. The degradation ability of the expression product to aflatoxin AFB₁ was tested by enzymatic hydrolysis. The results showed that the ADTZ gene was successfully amplified from the moldy maize suspension. The full length of the ADTZ gene sequence was 2 088 bp, and the similarity with the reported ADTZ gene was 99%. The gene can be fused and expressed in E. coli. The protein size of the expressed product was 118.5 kDa. The crude enzyme solution of recombinant E. coli could degrade AFB₁ in mildewed maize, and the degradation rate reached 77.69%.