Generally, the causes of sudden acne on the face are inadequate facial cleansing, improper diet, endocrine disorders, infections and so on. 1. Inadequate facial cleansing: not doing a good job of skin cleansing in daily life, which in turn leads to the secretion of a large amount of oil, blocking pores, resulting in acne. 2. Improper diet: usually like to eat sweets, diet too greasy spicy, will cause sebaceous gland hyperfunction, secretion of a large amount of oil, so blocking the pores caused by long acne. 3. Endocrine disorders: female endocrine dysfunction, the body’s androgen secretion is too much, will also lead to a large amount of skin oil, thus appearing on the face of the sudden growth of acne. 4. Infection: If the body resistance is low, it is easy to get infected with Propionibacterium acnes, resulting in sudden acne. Irregular work and rest and emotional instability can also lead to acne. It is recommended that patients go to the hospital in time, under the guidance of the doctor to clarify the specific causes of sudden acne, and then treat the symptoms to achieve better results.