There is no way to tell if a painless ulcer is syphilis; it should be judged based on the appropriate tests. Syphilis is a chronic, systemic sexually transmitted disease (STD) caused by infection with the syphilis spirochete. The main mode of transmission is sexual. It is categorized as Stage I, Stage II and Stage III syphilis. Stage I syphilis manifests itself as a hard chancre, which is usually a painless, itchless, round or oval ulcer with clear borders, but it cannot be used as a basis for diagnosis, and should be examined accordingly in a hospital, such as direct examination of the syphilis spirochete and syphilis serology tests, and if the spirochete is found to be positive in the test or the syphilis serology test, then only then can it be proved to be infected with syphilis. The body appeared painless ulcers recommend timely medical perfect related examination clear diagnosis, early detection, early treatment, so as not to delay the condition.