Abstract: At present，750 antimicrobial peptides have been successfully isolated from the biological community，of which with antitumor activity account for about 13.1%. The antibacterial peptides derived from amphibians and fish are about 13.3% and 9.3%，respectively. Fish and amphibians are the most primitive vertebrate，and most of them rely on the gills，skin and intestinal breathing. Due to their extremely fragile acquired immune system，they have a powerful innate immune system to avoid the infection of the pathogen，thus the antimicrobial peptides distributed in different parts have become the important component of first defense line of broad-spectrum in these lower organisms. This paper reviewed the broad-spectrum antibacterial activity and immune regulation ability of antibacterial peptides such as moronecidin，epinecidin-1，paradaxin，and misgurin distributed in hybrid striped bass，Epinephelus coioides，Pardachirus marmoratus，and Misgurnus anguillicaudatusis，as well as antibacterial spectrum of smelly frog antimicrobial peptide. For instance，the moronecidin can kill all gram positive bacteria and some gram negative bacteria. Epinecidin-1 can effectively prevent the infection of vulnificus（Vibrio vulnificus）in grouper and kill the nervous necrosis virus. Paradaxin reveals the antitumor activities. Misgurin has strong bactericidal ability. Antibacterial peptides from the smelly frog can kill Candida albicans. Then，the paper summarized the antibacterial peptides successfully expressed in Pichia pastoris and those derived from fish and amphibian of having antiviral and antitumor activities. Finally，the paper discussed the problems and solutions in the application of these antibacterial peptides，providing a theoretical basis for green and effective antibacterial peptide drugs in various fields to play a great role.

Key words: antimicrobial peptides, antimicrobial spectrum, Pichia pastoris