A pimple on the chest may be caused by folliculitis, lipoma, epidermal cysts, common warts and other diseases. 1. Folliculitis: it is an inflammation that occurs in the hair follicles, which can be caused by bacterial and fungal infections. The main manifestation is the formation of pimples centered on the hair follicles, which can be distributed or appear in pieces. 2. Lipoma: it is a kind of benign tumor of soft tissue, which is often a single or multi-focal limited lump under the skin with small volume. Often there are no obvious symptoms, but there may be pain or corresponding symptoms caused by compression of surrounding tissues when the tumor grows. 3. Epidermoid cyst: it is a kind of cyst containing keratin in the dermis, which occurs in the head, face, chest and back, and is single in many cases and multiple in a few cases. The center of the cyst may have a black, pinpoint-sized indentation, and white contents may be squeezed out. 4. common warts: caused by the human papilloma virus infection of a contagious skin surface of the superfluous organisms, usually soybean size, shaped like a pimple, can be gray-brown, brown and other colors. The first thing you need to do is to get a good deal of money to pay for the services you need.