Red bumps on the chest may be caused by acne, folliculitis, eczema and other diseases. 1. Acne: The cause may be related to the large amount of sebum secretion, sebaceous gland duct keratinization, Propionibacterium acnes infection and other factors. Patients will have localized pimples and papules, which can be seen on the chest and back. 2. Folliculitis: the cause of the disease is mainly related to Staphylococcus aureus infection, hair plucking, excessive sweating and other factors can also trigger the disease. Patients will appear locally with red papules centered on hair follicles, which can be seen on the head and face, buttocks, trunk and other parts of the body. 3. Eczema: the cause of the disease is not clear, may be related to genetic, immune abnormalities, hormone level changes and other factors. Patients will have localized erythema, papules, papules and other symptoms, which can be distributed in any part of the body surface. The causes of red bumps on the chest are more, it is recommended to go to a regular hospital to check, clarify the cause of the disease, and follow the doctor’s instructions for treatment.