There are no special signs that a man has syphilis. To determine if you have syphilis, you have to rely on past sexual misconduct, typical symptoms and laboratory tests. Syphilis is a chronic, multisystemic sexually transmitted disease caused by the syphilis spirochete, and there are no early signs. Sexual transmission is the primary mode of transmission; therefore, patients with syphilis usually have a typical history of unclean sexual intercourse. According to the stage of progression, it is divided into three phases, with phase I being the earliest clinical symptom. It usually strikes two to three weeks after infection, with no special systemic manifestations, and is mainly characterized by a hard chancre on the external genitalia and perianal area. At first it is a single erythema, papule, with the progress of the disease can form painless vesicles. If you have high-risk behavior, you should also go to the hospital in time to improve the syphilis related examination, which is the main evidence of the diagnosis of syphilis.