Abstract: The effects of mannitol on cell redifferentiation and activities of indole acetic acid oxidase and peroxidase, glutathione S_transferase, and peroxidase in cells of wheat were investigated. The results showed that 16 g/L mannitol reduced the capacity of wheat cell redifferentiation, decreased the soluble protein content and the activity of indole acetic acid peroxidase and glutathione S_transferase, enhanced the activity of indole acetic acid oxidase and peroxidase.