Abstract: Reactive oxygen species （ROS）, generated in the metabolism process of aerobic organisms, can induce oxidative damages in the body. These organisms are all equipped with an excellent defense system to protect themselves and antioxidant enzymes play an important role in the system. Parasitic trematodes have to eliminate ROS not only from themselves but also from the immune system of their hosts. To better understand the structures and specialities of the antioxidant enzymes in trematodes is conducive to the study on reproductive physiology of trematode and on drug and vaccine development. This paper summarizes the research progress on the family of antioxidant enzymes in trematodes including glutathione peroxidase （GPx）, superoxide dismutase （SOD） and peroxiredoxin （PRx） in the past decades.

Key words: Antioxidant enzyme, Trematode, Reactive oxygen species（ROS）