In this case report, we present a pediatric case of lymphomatoid granulomatosis (LG) with onset just after the completion of chemotherapy for childhood acute myeloid leukemia (AML). After the completion of maintenance therapy, the patient was admitted to our clinic with a complaint of cough. Radiologic examinations revealed nodular lesions in lungs, liver, and kidney. His bone marrow was in remission. The histopathologic examination of the open lung biopsy was consistent with LG. He received only one cycle of cyclophosphamide and high-dose methyl prednisolone treatment and continued to receive interferon (IFN) alpha-2b therapy for 18 months. This treatment regimen resulted in an excellent response. In conclusion, LG may occur after the treatment of pediatric AML as a rare complication and IFN alpha-2b may be an effective treatment choice in these patients.