If suffering from melanoma not only affects the beauty but also endangers the life, those black lumps on the patient’s skin make the patient worry, so we need to have more understanding of melanoma to avoid the gradual deterioration of the disease. A way to determine melanoma is the deepening or hypopigmentation of the rash. There may be light brown-intense brown-black, dark red-red-purple, gray-blue-green-gray-blue, or even loss of pigment, which are the early symptoms of melanoma. Second, the early symptom of melanoma is unclear boundary around the rash. Or one side is clear while the other side is blurred, giving a vague feeling. Third, the rash is asymmetrical. One side of the rash is more stable, and the way to judge melanoma is that the other side expands to the periphery and shows irregularity and epidermal roughness, which is also an early symptom of melanoma. Fourthly, the rash grows rapidly in a short period of time. it grows exponentially within 1 to 2 months. The diameter of the rash of congenital pigmented nevus is larger than 6 mm, and the way to judge melanoma is especially if it occurs in the palm of the hand or the sole of the foot, if the diameter of the pigmented nevus is more than 15 mm, it already suggests the possibility of malignancy. Fifth, is whether the rash is elevated. The early symptoms of melanoma rash is not elevated on the surface at first, then slightly elevated and gradually formed nodules. Or the surface has vesicles, crusts, pus, running water, especially bloody water. This is one of the ways to determine melanoma.