The possible causes of rough and grainy neck skin include filiform warts, acanthosis nigricans, and chronic simple moss. 1. Filiform warts: when the patient’s neck area skin is infected by human papilloma virus, it will lead to the occurrence of filiform warts, which can form multiple small protruding warts on the neck, resulting in the neck area of the skin is not smooth and granular to the touch, this kind of patient can be frozen, laser and other physical therapy to help treatment. 2. Acanthosis nigricans: obesity, endocrine abnormalities, tumors and other factors can cause acanthosis nigricans, resulting in the neck, armpits and other parts of the local melanin pigmentation, and the surface of the pigmentation can be a lot of small, velvet-like protrusions, resulting in the neck part of the skin to touch the roughness of the granularity of the skin, such patients need to actively search for and treat the cause of the disease. 3. Chronic lichen simplex: If the roughness and granularity of the skin mainly occurs on the back of the neck and is accompanied by more obvious itching symptoms, staying up late, excessive mental stress, spicy diet, scratching and other irritating factors will make the relevant symptoms worse, then it may be the neck area of the chronic lichen simplex, which can be treated by applying topical haldolizone cream. All of the above medications should be administered under the guidance of a doctor to avoid adverse reactions. It is recommended that the patient should seek medical advice from the doctor in a timely manner.