We report a case of delayed brain atrophy after electrical injury. A 12-year-old boy sustained extensive burns by touching a high-voltage power line. The burn area comprised more than 60% TBSA, and he subsequently underwent several surgical procedures. Two months later, he suddenly developed seizures. Initial findings on magnetic resonance imaging showed diffuse cortical damage in the left brain. Two months later, motor aphasia appeared, and a second magnetic resonance imaging scan showed atrophy in the left temporal and frontal lobes. Owing to speech rehabilitation, the patient gradually recovered his capacity for speech. Eight months later, his speech was almost perfect. We believe that because the patient was young, early speech rehabilitation was effective.