If the surface of a mole is rough and raised like a scab, it is painless and itchy, and can be considered as a malignant nevus, sebaceous nevus or seborrheic keratosis. 1. Malignant change of nevus: when there is deepening of pigmentation, increase in pigmentation, ulceration and bleeding of junctional nevus or mixed hemorrhoids, it may cause roughness of nevus, and then malignant change should be considered. 2. Sebaceous nevus: a disease mainly characterized by sebaceous gland hyperplasia, which can be seen as yellow or brown wart-like, nodular or flap-like lesions, banded plaques or ovoid, with rough surface. 3. Seborrheic keratosis: it may be related to chronic inflammatory stimulation, sun exposure and other reasons, it can be seen on the back of the hand, chest, back and other places of the skin, the lesions are yellow or light brown plaques or flat papules that can be higher than the surface of the skin, and there are pathological manifestations of hyperkeratosis and hypertrophy of the stratum spinosum. There are abnormal changes in the skin on the surface of the mole, it is recommended to go to the hospital specialist in time and follow the doctor’s instructions for treatment, so as not to delay the condition.