The sebaceous glands secrete more oil when the face is oily. The sebaceous glands are affected by genetic factors, endocrine disorders, environmental factors, dietary factors and work and rest. 1. Genetic factors: Sebaceous gland secretion is affected by genetic factors. 2. Endocrine disorders: endocrine disorders can cause an increase in androgen secretion, which stimulates the sebaceous glands of the hair follicles to increase secretion, and there will be a lot of oil on the face. 3. Environmental factors: high temperature in summer, sebum secretion will increase accordingly. 4. Dietary factors: greasy, fried, sweet, spicy food eat more, facial oil secretion will increase. 5. Work and rest: Long-term irregular life, such as staying up late, poor rest, will also increase the skin’s oil secretion. Improper use of skin care products and excessive cleaning can also cause severe facial oil. For the oil on the face, patients need to go to the regular hospital under the guidance of a dermatologist for appropriate treatment.