Abstract: 【Objective】 To get a thorough understanding about the distribution and dynamic changes of the glutathione peroxidase (GPx) activity in pigs.【Method】 Using three varieties of pigs as the subject, GPx activities of different tissues and whole blood from pig with different species, genders, age periods and health statuses were determined in this study.【Result and conclusion】 The result showed that the GPx activity of whole blood from Lantang or Landrace pigs was slowly rising from 26 to 150 d, reaching a maximum at 150 d. The GPx activity of Lantang pigs was significantly higher than that of Landrace pigs during the periods of 30 and 90 d（P<0.05）and no significant difference in the other periods. The GPx activity of hybrid boars(Duroc×Yorkshire×Landrace) was significantly higher than that of sows（P<0.05）; the GPx activity of healthy pigs (Duroc×Yorkshire×Landrace) was significantly higher than that of sick ones（P<0.05）. Samples from different tissues revealed that kidney, spleen, liver, lung, heart and ileum showed a higher Gpx activity and these tissues can be used as ideal raw materials for extracting GPx.