To evaluate the safety of oral cabamazepine during breast milk feeding. The carbamazepine concentration in breast milk of one epilepsy maternal patient was assayed by high performance liquid chromatography, and the literature was reviewed to find the nursing evidence in the use of cabamazepine. The carbamazepine concentration in breast milk ranged from 0.34-0.86 mg/L. The neonate daily dose intake was estimated ranging from 0.34 mg to 0.86 mg through breast-feeding in theory. The literature showed that carbamazepine was generally considered safe for use during breast feeding; however, adverse effects should be monitored as recommended. It is better to avoid feeding at high concentration level to minimize the harm of carbamazepine to the baby.