It is a very common clinical symptom and has many causes, as follows: 1. sebum overflow, because the location of the chest hair follicle sebaceous glands are more vigorous, easy to produce more sebum. 2. may be related to excessive secretion of androgens, sebaceous gland synthesis and excretion, endocrine disruption, hair follicle mouth blockage, Propionibacterium acnes infection, etc. 3. irregular daily routine, eating too much spicy, greasy, irritating food and sweet food, etc. These are also possible causes of chest acne, These are also possible causes of acne on the chest. The above are the common reasons for chest acne, you can take oral isotretinoin, while topical Adapalene ointment for treatment. You should pay more attention to rest and not stay up late to reduce the occurrence of chest acne.