Abstract: Objective　To discuss the clinical features, diagnosis and treatment of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome in children. Methods  The clinical features and treatment process of two children with MELAS were retrospectively analyzed. Results　The main clinical features of MELAS were stroke-like episodes, seizure, visual anomaly and lactic acidosis. Cephalic MRI findings performed during episode periods were in accord with the typical radiographic features of MELAS. Gene testing on the two children and their mothers showed the point mutation of A3243G in mitochondrial genome. The symptoms were improved significantly after energy supply and corticosteroid treatment. Conclusions  MELAS syndrome is easy to be misdiagnosed due to the varied clinical features. The diagnosis depends on the musclebiopsy and gene testing. Corticosteroid therapy is effective for MELAS syndrome.