Black acne marks on the back are usually caused by post-inflammatory hyperpigmentation, resulting in melanin precipitation. Patients are advised to eliminate them through general treatment, topical medication or skin care products, and laser treatment under the guidance of a doctor. 1. General treatment: patients should do a good job of sun protection in daily life to avoid ultraviolet radiation leading to increased pigmentation. Meanwhile, avoid using irritating skin care products. 2. Topical medication or skin care products: For black acne marks on the back, patients can use topical retinoic acid cream and polysulfonic acid mucopolysaccharide cream. Patients can also use topical skin care products containing vitamin C, arbutin and other ingredients. 3. Laser treatment: For black acne marks on the back, it is also possible to treat them with intense pulsed lasers or non-ablative lasers. For patients with black acne marks on the back, it is recommended that they go to a regular hospital in time for examination and standardized treatment under the guidance of a professional doctor.