If you have small red spots on your genitals, you need to go to the hospital for relevant tests to clarify the cause. Firstly, allergic erythema, commonly associated with systemic allergic reactions, can manifest locally as small red dots on the genitals or other parts of the body, accompanied by local itching, or with local pain and other symptoms. In case of severe allergy, it can also be accompanied by local edema and exudation, which needs to be determined by allergen determination. Second, genital infections, such as circumcision and glansitis, can appear as localized red spots, with the aggravation of inflammation, the red spots expand, forming red spots, accompanied by local swelling, pain, or with local exudation or erosion and other reactions, need to carry out relevant pathogenetic testing and physical examination to clarify the presence of local infection. Third, when there is a rash or external genital herpes, or when there is human papillomavirus infection, there can be localized small red spots. Small herpes-like changes, or papule-like changes, or granuloma-like changes can occur, and further development can result in the growth of corresponding lesions, such as herpes in the form of patches, or papillomatous sarcomas that gradually increase in size, which require relevant viral testing to further confirm the diagnosis.