Sebaceous cysts can be caused by sebaceous cysts, soft skin fibromas, bacterial infections and sexually transmitted diseases. 1. Sebaceous cysts: the penis is in a hot and humid environment for a long time, which can cause the local sebaceous glands to secrete exuberantly and trigger folliculitis, without timely diagnosis and treatment of cysts are easy to form, which can be seen on the penis, skin flabbergasted performance. 2. Dermatofibroma: Dermatofibroma is a benign tumor, mainly due to the abnormal proliferation of cells in the penis and other factors, there can be skin flab-like changes. 3. Bacterial infection: Long-term lack of attention to penile hygiene and cleanliness can lead to local bacterial infection and inflammation, local inflammatory lesions can occur, resulting in the appearance of the penis skin flab. 4. Sexually transmitted diseases: may be due to the occurrence of warts and other sexually transmitted diseases, mostly caused by the infection of human papillomavirus, can appear in the penis of vegetable pattern skin flabs, with the progress of the disease can be constantly increasing, and present multiple. When the penis long skin flab should be timely medical treatment, under the guidance of specialized doctors to actively carry out appropriate treatment, help to alleviate the discomfort of the symptoms as soon as possible.