Acute encephalopathy is a disease in which the body reacts to pathogens such as viruses, resulting in sudden swelling of the brain. Acute encephalopathy often causes convulsions and disturbance of consciousness, and there is a possibility that sequelae remain. Therefore, it is important to treat the disease accurately based on the symptoms and test results. After treatment, there are many cases where aftereffects such as intellectual disability, movement disorders, and epilepsy remain. In this study, subjects with residual aftereffects of acute encephalopathy were given 9 courses of aromatherapy treatment approximately once every 7 days, the results were recorded using the KK scale method, and changes in QOL were observed and analyzed.