Objective: To explore relationship of tumor necrosis factor α(TNF-α) with the clinical course in the central nervous system (CNS) of experimental autoimmune encephalomyelitis (EAE) in mice

and to explore the mechanism and effects of Yishen Daluo decoction (YDD) for treatment of EAE. Method: Ninety-five SJL/J mice were randomly divided into normal group

predinisone 3.9 mg·kg-1group

YDD 20 g·kg-1 group and YDD 20 g·kg-1 +predinisone 3.9 mg·kg-1 group. Immunohistochemistry and western blot were used to explore the expression of TNF-α in the CNS in SJL/J mice after 15 d administretion. Result: Compared with model group

YDD could reduce the relapse rate of EAE

improve the neurological function score (P<0.05). Compared with model group

the content in central nervous system of TNF-α was reduced in normal group

predinisone-treated group

YDD group

predinisone-YDD complex treated group (P<0.05). Conclusion: TNF-α mediated inflammatory cascade might play an important role in the mechanism of CNS inflammatory infiltration and axonal injury in EAE. Treatment with YDD can reduce the relapse rate of EAE

improve the neurological function score. The therapeutic mechanism of YDD is proposed by regulating the level of TNF-α.