Neck acne may be caused by folliculitis, contact dermatitis, epidermal cysts and other diseases. 1. Folliculitis: its etiology is related to skin injury, excessive sweating, pathogen infection and other factors. Patients may have localized pimples, pustules, pain and other symptoms, manifested as neck acne. 2. Contact dermatitis: its cause is mainly skin contact with irritating substances or allergic substances, leading to inflammatory reactions in the skin. Patients may have erythema, papules, edema, itching and other symptoms in the neck area, manifested as neck acne. 3. Epidermoid cysts: they are benign skin cysts that contain a large amount of keratin. Epidermal cysts can occur in any part of the body, the symptoms are raised skin mass, manifested as neck acne. There are many reasons that lead to acne on the neck of patients, and it is recommended that patients go to regular hospitals to clarify the cause of the disease.