Accumulating evidence strongly suggests that many polysaccharides have immunomodulatory activity usually accompanying with antioxidant activity, such as polysaccharides from Dietary litchi pulp , Cordyceps militaris , and Polygoni Multiflori Radix . The CY-induced overproduction of oxidant compounds associates with the inflammatory response, and can lead to reduced function of virtually all immune cells . Aberrant production or regulation of reactive oxygen species (ROS) cause tissue damage and loss of function in a number of tissues and organs . The lipid peroxidation decreases membrane fluidity, which adversely affects immune responses. Therefore, the relevance of antioxidants is particularly critical for the functionality of immune system . The antioxidant enzymes such as SOD, CAT and GSH-Px in tissues can convert active oxygen molecules into non-toxic compounds to protect against oxidative stress and tissue damage. T-AOC reflects or represents the capacity of the non-enzymatic antioxidant defense system. MDA, involved in forming lipid radicals and oxygen uptake, is a marker for endogenous lipid peroxidation . In our present study, CY treatment resulted in the suppression of T-AOC, SOD, CAT and GSH-Px in heart, liver and kidney as well as an increase in the MDA level. However, the treatment of AHG (1, 5 and 10 mg/kg) significantly increased the levels of T-AOC, SOD, CAT and GSH-Px as well as decreased the MDA levels in tested tissues. These findings showed that AHG can be effective in scavenging various types of oxygen free radicals and their products, indicating that AHG was able to protect against oxidative stress induced by CY in vivo. Further investigation is necessary to verify the precise repair mechanism of AHG and the interaction with other medicines.