Xeroderma Pigmentosum(XP) is a rare, autosomal recessive disorder characterized by photosensitivity, cutaneous pigmentary changes, premature skin ageing, and the development of various cutaneous and internal malignancies at an early age. The basic underlying genetic abnormality is a nucleotide excision repair (NER) defect leading to defective repair of DNA damaged by ultraviolet(UV) radiation.most patients with XP are not abnormally sensitive to therapeutic radiation. We herein describe the clinical response with radiation therapy for malignant melanoma in a child with XP. This case is being presented because of rare association of Malignant Melanoma with Xeroderma Pigmentosum patients in India. However, radiation therapy should be used with caution in XP patients with an anticipated prolonged life expectancy, because the late side effects of ionizing radiation in XP are not well known. This case is reported to illustrate the use of ionizing radiation in the treatment of malignancies in XP patients in addition to other management strategies available for this incurable disease entity