Objective To explore the possible mechanism of anti-epilepsy effect of Dingxian Decoction（定痫汤）. Methods A total of 66 rats were randomly divided into model group

Dingxian Decoction group and Dingxian Decoction + K252 a group

with 22 rats in each group. Lithium pilocarpine was used to establish rat epilepsy model

and 22 healthy rats were set as normal group. K252 a-antagonist tyrosine kinase receptor B（TrkB） was injected into lateral ventricles of rats in Dingxian Decoction + K252 a group one week before the establishment of model

5 μl each time and once a day for a week;Dingxian Decoction group and Dingxian Decoction + K252 a group were given 2 ml Dingxian Decoction through lavage at the concentration of 1. 55 g/ml 1 hour after the establishment of model

while normal group and the model group were given the same volume of normal saline once a day for 6 weeks. Eleven rats in each group were monitored by electroencephalogram（EEG） and the latency

frequency and duration of spontaneous epileptic recurrence were recorded. The expression of brain-derived neurotrophic factor（BDNF） in hippocampus was detected in the other 11 rats of each group. Results There was no spontaneous epilepsy recurrences in the normal group

while 9 rats in the model group

5 rats in the Dingxian Decoction group and 8 rats in the Dingxian Decoction +K252 group showed spontaneous epilepsy recurrence. Compared with the model group

the latency of spontaneous recurrence of epilepsy in Dingxian Decoction group was significantly prolonged

the frequency and duration of epilepsy were significantly reduced

and the expression of BDNF protein in hippocampus was decreased（P < 0. 01）. Compared with Dingxian Decoction group

the frequency and duration of spontaneous epilepsy recurrence in Dingxian Decoction + K252 group were increased

and the latency was shortened and the expression of BDNF was decreased（P < 0. 01）. Conclusion Dingxian Decoction may play an anti-epileptic role by regulating BDNF/Trk B pathway.