Hair growth on a mole is not necessarily malignant. Whether a mole has hair or not is related to the type of mole and has nothing to do with its benign or malignant nature, therefore, you cannot judge whether a mole is malignant or not by whether it has hair or not. Generally speaking, a hairy mole is an intradermal nevus, which belongs to a kind of pigmented nevus, and is a benign tumor caused by proliferation of melanocytes in the skin, manifesting itself as a flat or higher-than-skin-plane hyperplasia, which can be in the form of nodules, warts, papillomas, etc., and is brown or black in color, with clear boundaries, often with hair growth, and usually does not need any special treatment. When there are symptoms such as swelling, itching, erosion, ulceration and pain, there may be a tendency of cancerous transformation, so it is recommended to seek medical treatment in time and undergo surgical treatment if necessary. Hair growth on moles is not a symptom of malignant transformation, it is suggested that people in this situation do not need to be overly nervous, the chance of malignant transformation of intradermal nevus is very low, but if there are symptoms of cancerous transformation, it is necessary to consult a doctor in time.