Abstract: Many new Helicobacter species have been detected from animals or poultry since the discovery of Helicobacter pylori from the human gastric mucosa, many of them are identified to be pathogenic to animals or human, others are potential pathogenic or unclear. This paper summarizes the biological characteristics of Helicobacter, the new Helicobacter species detected in recent years and their pathogenicity to provide reference for the prevention and control of the diseases caused by Helicobacter spp.