Abstract: The aim was to study the function of gp37 in the host recognition of phage Bp7. The Cterminal gene of tail fiber protein gp37 of phage Bp7 was amplified by PCR, and then was cloned into pGEX6p1 plasmid. The recombinant plasmid pGEX6p1gp37 was transformed into BL21, and then induced by IPTG. The polyclonal antibodies against GST·gp37 were prepared and used to study phage reproduction. The results of SDSPAGE and Western blot showed that a 67 kD GSTtagged fusion protein was obtained successfully. The polyclonal antibodies to gp37 of Bp7 could inhibit the reproductions of phages Bp3 and Bp7 obviously, while no significant effects on phages Bp2, Bp5 and Bp6 were detected. Antibodies to gp37 of Bp7 could facilitate the reproduction of phage Bp4. The results verified that gp37 participated in the host recognition of Bp7.