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elanoma is a highly malignant tumor of melanocytes and predominantly involves the skin. It is the most deadly form of skin cancers. The incidence of melanoma has been steadily increasing in recent decades, and risk factors associated with melanoma development have attracted more and more attention from researchers in this field. Ultraviolet radiation ��UVR�� exposure, in the form of intermittent heavy exposure and severe sunburns in childhood, is believed to be the most important environmental contribution to melanoma risk. Genetic determinants also modulate melanoma risk, probably to a greater extent than environmental exposure. Two high-penetrance melanoma susceptibility genes, CDKN2A and CDK4, have so far been identified. Phenotypic markers of high-risk include skin color, hair color, pigmented nevi, etc. Other risk factors include socioeconomic status, occupations and ingestion of therapeutic drugs. Genetic detection and long-term clinical follow-up may reduce the risk for melanoma.