Background: Parkinsons disease is a chronic neurological disorder which may be due to reduction in the dopaminergic neurons in the brain. However, Agaricus blazei is a rich source of natural antioxidants.
 Aim: In this study, antiparkinsonian activity of Agaricus blazei Murill was evaluated using different animal models.
 Method: Antiparkinsonian activity was evaluated using two different doses (273 mg/kg and 819 mg/kg) of Agaricus blazei Murill. Rotenone and sunflower oil were used as positive and negative control, respectively. Catalepsy test, rotarod test, exploratory behavior test (rearing) and locomotor activity test were conducted to observe antiparkinsonian activity of the drug in rats.
 Result: The results of the animal models were confirmed by determining the levels of reduced glutathione, total protein, thiobarbituric acid reactive substances (TBARS) and nitric oxide in the animal brain. Pretreatment with Agaricus blazei Murill, showed marked reduction in rotenone-induced catalepsy and a significant increase in exploratory behavior, muscular activity, and locomotor activity in rats. Agaricus blazei Murill has also shown extremely significant effect in decreasing the oxidative stress in the animal brain by increasing the brain levels of reduced GSH and total proteins and decreasing the levels of nitrite and TBARS.
 Conclusion: The results of rotenone-induced catalepsy, exploratory behavior, rotarod test and locomotor activity showed that Agaricus blazei Murill exerts a significant ameliorative effect on Parkinson’s disease in rats.