Abstract: Objective To construct recombinant plasmid of streptavidin (SA) and autophagy-related genes Beclin1 fusion gene （Beclin 1）and to express and purify SA-Beclin1 fusion protein. Methods The natural core SA sequence and beclin1 gene were cloned into pQE80 to form the recombinant plasmid pQE80-SA-Beclin 1. The expression of fusion protein was induced by IPTG, purified by Ni-NTA agarose and detected by Western-blot. Results The natural core SA was amplified by PCR, restriction enzyme digestion and sequencing results showed that the recombinant plasmid pQE80-SA-Beclin1 was successfully constructed. The fusion protein induced by IPTG was efficiently expressed in E．coli. Fusion protein was detected by SDS-PAGE and purified by Ni-NTA agarose with a molecular weight of 72 000 kD identified by Western blot. Conclusion The SA-Beclin1 fusion protein was successfully expressed and purified, which lay a good basis for further functional research and clinical application of beclin1．