The measles epidemic was observed in Ukraine during 20172019. According to WHO, in Ukraine there was registered the highest number of measles cases in Europe during that period [8]. Measles is characterized by an acute course with fever, maculopapular rash, cough, conjunctivitis and can lead to central nervous system complications (encephalitis, encephalomyelitis) and bronchopulmonary system complications (laryngotracheobronchitis, bronchiolitis, pneumonia). In immunocompetent patients, viremia ends after the end of clinical signs, in contrast to immunosuppressed individuals, who could develop viremia from one month up to a year. We have described a case of measles inclusion body encephalitis (MIBE) or subacute measles encephalitis (SME) in an unvaccinated child with an acute lymphoblastic leukemia (ALL). The diagnosis was confirmed by the synthesis of IgG antibodies to the measles virus in the cerebrospinal fluid and by the MRI results. The disease had a dramatic course and ended in death.