Ｏｂｊｅｃｔｉｖｅ　This study was to determine the values for 95% effective dose(ED95) of rocuronium in epilepsy patients.　Methods　Fourty epilepsy patients between 18 and 65 years of age, with ASA physical status classicfication Ⅰ or Ⅱ, undergoing elective surgery were enrolled. All patients were randomly divided into four groups(n=10) and were received (120, 180, 240 μg/kg and 300 μg/kg) rocuronium respectively. Neuromuscular monitoring of the ulnar nerve consisted of surface electrode stimulation and force transduction of the adductor pollicis muscle. Neuromuscular block was assessed by the percentages of maximum suppression in T1 of train of four stimulation(TOF). The data of maximum suppression in T1 were transformed into probit and dosage of rocuromium were transformed into logarithm. The onset time of rocuromium was recorded. The dose-effect curve of rocuronium was set up with linear regression method. And the ED95 value of rocuromium was calculated.　Results　There was not a significant variation in onset time among four groups(P>0.05). The maximum suppression in T1 were increased in group of higher dose(P<0.05), however there was no significant different between group 240 μg/kg and group 300 μg/kg(P>0.05). The ED95 value of rocuromium in epilepsy patients is 445.3 μg/kg, and that was higher than normal people with 300 μg/kg ED95 value(P<0.05).　Conclusions　The ED95 value of rocuromium in epilepsy patients is higher than non-epilepsy patients. The present data support the larger dose rocuronium is needed in epilepsy patients.