Acanthosis nigricans is not necessarily diabetes. Acanthosis nigricans is a rare clinical skin condition characterized by velvety thickening and hyperpigmentation of the skin. Diabetes mellitus, on the other hand, is a disease characterized by insulin resistance and increased blood glucose. The development of acanthosis nigricans may be related to insulin resistance, but insulin resistance is not only a feature of diabetes, but is also prevalent in a wide range of human diseases and pathologies. However, the diabetic population has an elevated likelihood of developing acanthosis nigricans compared to the general population due to the prevalence of insulin resistance, and thus acanthosis nigricans is often seen manifesting in diabetic patients. However, acanthosis nigricans is not diabetes and the two should not be confused. Therefore, patients with acanthosis nigricans who want to determine whether they have diabetes should go to the hospital in a timely manner, complete the relevant examinations, and then give targeted treatment in a timely manner after a clear diagnosis.