Objective    To explore predictive value of electrocorticography (ECoG) on postoperative epilepsy in patients with intracranial tumors.     Methods    Totally 95 patients with intracranial tumors were admitted in our hospital and their ECoG signals were recorded pre- and post-operation. According to the variation of the amplitude and density of spike waves on ECoG before and a

fter operation

the patients were divided into 3 groups: group A who having more spike waves after tumors were removed

group B with the same amount and group C having lesser spike waves. The patients had a 4 years’ follow-up and the epilepsy were divided into postoperative early epilepsy and late epilepsy.     Results    ECoG showed that the patients in group A

group B and group C separately were 13 cases (13.68%)

37 cases (38.95%) and 45 cases (47.37%). There were 32 patients with early epilepsy

and among them

8 cases (61.54%）were from group A

13 cases(35.14%）from group B and 11 cases (24.44%) from group C. Significant difference was observed among the 3 groups with early epilepsy (Chi-sqaure=6.2

P

<

0.05). Seventeen patients（17.89%）who suffered late epilepsy were 1 (7.69%)

7 (18.92%) and 9 cases (20.00%) respectively in group A

group B

and group C (Chi-sqaure=1.04

P

>0.05).There are 7 patients of 32 patients with early epilepsy occurring  late epilepsy

and 10 of 63 patients with no early epilepsy (Chi-sqaure=0.93

P

>0.05).     Conclusion    The variety of ECoG on patients with intracranial tumors undergone surgery is helpful to prognosticate postoperative early epilepsy.