Objective: The aim of the study was to evaluate the etiology, treatment and prognosis of the malignant skin tumors in children. Methods: Twenty-one patients who had been diagnosed with malignant skin tumors between 1972 and 2003 were retrospectively analyzed. Age range was 0.5-20 years (median 9), and the male/female ratio was 12/9. We had nine (42.9%) patients with malignant melanoma, five (23.8%) with primary skin non-Hodgkin lymphoma, three (14.3%) with Kaposi sarcoma (KS), two (9.5%) with basal cell carcinoma (BCC), and two (9.5%) with squamous cell carcinoma (SCC). Results: We could define the etiologic factors in only nine (42.9%) patients. Two KS cases were associated with renal transplantation, two cases of malignant melanoma occurred within the area of giant hairy cell nevus, one melanoma patient previously had bone marrow transplantation due to Gricelli syndrome, one patient with BCC had xeroderma pigmentosum and the other BCC had got radiotherapy due to previous diagnosis of medulloblastoma. One SCC patient also had xeroderma pigmentosum and the other had previous skin burn. Overall survival rate was 77%. Melanoma patients were treated successfully with high-dose interferon. Conclusion: Although malignant skin tumors are rare in childhood, the prognosis is relatively better than it is for adults. Malignant melanoma was the most frequent tumor. Forty-three per cent of our patients had an underlying defect in their immune barriers which is thought to be responsible for the development of their malignancies.