Pimples on the forehead, usually referred to as acne, is a chronic inflammatory skin disease of the sebaceous gland units of hair follicles. It is considered to be related to factors such as androgen levels, heredity, poor lifestyle and dietary habits, and keratinization of the follicular opening. 1. Androgen levels: The exact cause of acne is not yet fully understood. For example, high androgen levels and abnormal androgen receptors in the body may affect sebum secretion, leading to excessive sebum secretion and the possible formation of acne. 2. Heredity: Parents or grandparents in the family often had acne when they were young. Their children may develop the above condition due to the influence of genetic factors. 3. Lifestyle and dietary habits: Frequent consumption of spicy and stimulating, dairy products, fried foods, sweets, etc. may increase the secretion of sebaceous glands. Often working overtime and staying up late, excessive mental stress, using oily cosmetics, washing the face too often, occupational exposure, etc., are also the main causes of forehead acne. 4. Keratinization of follicular orifices: Abnormal keratinization of follicular sebaceous gland ducts can affect sebum secretion and lead to sebum retention in the local area. Infection by Propionibacterium acnes may form acne. For forehead acne, it is recommended to consult the dermatology department of a hospital for standardized treatment under the guidance of a doctor.