Malignant melanoma is a malignant tumor that develops from melanocytes. Because of its strong tendency for early metastasis, it is considered one of the most malignant skin and mucous membrane tumors. Worldwide melanoma incidence has been steadily rising over the years. The most important factors in the development of melanoma are ultraviolet light (UV) exposure, familial predisposition, the number and type of nevi, skin type and pigmentation, and immunosuppression. Just like with any other disease, prevention is the key factor in the reduction of risk of melanoma development. Education on responsible consideration of personal health and regular self-examination of pigmented nevi are also of great importance. Early diagnosis and treatment are the most important factors of a beneficial prognosis. Regular (monthly) skin self - examinations are essential for an early detection of a melanoma. To conduct proper self-examination it is necessary to visually inspect the whole body, from head to toe, frontally, laterally and posteriorlly, not forgetting the scalp, earlobes and sex organs. The “ABCDE” method indicates signs and symptoms of changes that should be considered when performing the self-examination of nevi. These are: changes from a previously regular and symmetrical shape of a nevus into an irregular and asymmetrical shape (A – asymmetry); irregular delineation of the surrounding skin on the previously clearly delineated nevus (B – border); changes in pigmentation or irregular coloring of a previously monochromatic nevus (C – color), changes in size of a nevus (D – diameter); elevation - enlarged, evolved or elevated nevus (E – elevation). Apart from these five main symptoms of nevus change, it is also important to note any inflammation, erosion or bleeding of the nevus, as well as any subjective sensations of itching and pain of the nevus. Any changes in pigmentation or coloring of the nevus should be taken seriously and closely monitored. Family and personal medical history, detailed clinical examinations, histopathological diagnosis and dermoscopy are all essential for diagnostics.