Varicella-zoster virus infection can lead to severe illness in immunocompromised patients. Further the mortality rate of disseminated varicella infection is extremely high particularly in immunocompromised children. We report a case of disseminated varicella infection in a child with acute lymphoblastic leukemia who was receiving chemotherapy, but was initially admitted with only for acute abdominal pain. The patient rapidly developed severe complications, including acute respiratory distress syndrome, acute hepatitis, disseminated intravascular coagulation, and encephalopathy. Acyclovir is a highly potent inhibitor of varicella-zoster virus infection. However, owing to rapid disease progression, it might not be sufficient to control a disseminated varicella infection, especially in immunocompromised patients. Immunoglobulin neutralize virus invasion and suppress viremia, acting synergistically with acyclovir. In this case, early administration of acyclovir and a high-dose of immunoglobulin, combined with mechanical respiratory support, proved adequate for treatment of this severe illness.