A nerve-sheath myxoma beneath the dermis in the arm of a 5-year-old boy is reported. The tumor had developed on the site of chicken-pox vaccination the patient had received 2 years previously, and a foreign-body granuloma involving a nerve-fiber bundle was seen adjavent to the tumor. On the basis of previous reports, it is doubtful whether the varicella-zoster virus is tumorigenic. The present case suggests a possible relationship between the development of this tumor and factors associated with the vaccination.