Purpose : Benign childhood epilepsy with centrotemporal spikes (BCECTS) is the most common and favorable pediatric focal epilepsy syndrome. Only recurrent seizures need antiepileptic drugs (AEDs) and usually respond well to AEDs. This study was purposed to determine the risk factors associated with poor responders to the initial therapy. Methods : Total 149 patients with BCECTS were enrolled and reviewed retrospectively at Korea University Medical Center between January 2008 and March 2014. We analyzed the patients into two groups by administration of AEDs, 1) one is treated without or with one AED and 2) the other with two or more AEDs. Clinical characteristics such as age of seizure onset, initial drug, history of previous febrile seizures and EEG (electroencephalogram) findings were studied through medical records. Results : Of the 149 patients, 123 (82.6%) were controlled successfully with less than two AEDs, and 26 (17.4%) needed two or more AEDs to control seizures. Early onset of seizures, presence of febrile seizure history and additional generalized epileptiform discharges on EEG were significantly associated with poor response to the initial AED ( P0.05). On multivariate analysis, only early onset of seizure than 5 years old was independent risk factor (odds : 3.178) of poor response to initial therapy ( P=0.012). The presence of additional focal epileptiform discharges on EEG, brain MRI abnormalities, mental retardation and family history of febrile seizures or epilepsy were not associated with response to AEDs. Conclusions : This study showed that about 17% of patients with BCECTS were poor responder to initial AED therapy. The factors to predict a poor response to initial AED was early onset of seizure than 5 years old.