Dark and rough skin on the neck may be caused by acanthosis nigricans, dermatitis, and dry skin dehydration. 1. Acanthosis nigricans: a rare skin disease, mainly characterized by excessive skin pigmentation, velvety thickening, the affected area of the skin color deepens to light gray, light brown or dark brown dry, rough and hypertrophic. 2. Dermatitis: generalized to various types of skin inflammation, commonly papules, papules, blisters, erythema, scales, vesicles, ulcers, hyperpigmentation, roughness, etc., the patient may also be accompanied by itching, pain, burning sensation. 3. Skin dehydration and dryness: especially in the spring and fall seasons, skin dehydration and dryness can lead to dark and rough skin on the neck. There may be other reasons for the dark and rough skin on the neck, and it is recommended to go to the hospital in time for standardized diagnosis and treatment by a professional doctor.