The aim of this study was to investigate the effects of adjunctive lamotrigine (LTG) in refractory epilepsy in Taiwan, especially including patients who had undergone ineffective epileptic surgeries. Totally, 27 recruited children and adolescents with refractory epilepsy were treated with LTG add-on therapy, but 23 were enrolled statistically during 2 years period trial. Ten of the 23 patients (43.5%), including 5 undergoing epileptic surgeries, before had a > 50% reduction in seizure frequency. Surprisingly, LTG was found to have excellent response in six patients with Lennox-Gastaut Syndrome (LGS), 5 of whom had received anterior 2/3 callosotomy prior to the trial. Non-seizure related positive effects were presented in 3 patients, including greater alertness and attentiveness in 2 patients and improvement in mood in one patient. This open trial found that LTG was an effective add-on anti-epileptic drug (AED) in Taiwanese children and adolescents with refractory epilepsy and in cases with LGS even after ineffective callosotomy.