In order to investigate the prevalence of sexually transmitted viruses such as human papillomavirus (HPV) and herpes simplex virus (HSV) in Korean commercial sex workers (CSWs), we selected 188 CSWs (age range 20-44 years, median age 24 years) who regularly visited one public health center in Seoul, Korea. HPV genotypes were analyzed by using a HPV DNA Chip, and an enzyme-linked immunosorbent assay (ELISA) was used to detect type-specific IgG against HSV2 antibody identifying seropositivity for HSV2 infection. Polymerase chain reaction (PCR) was performed with specific primers to detect HPV and HSV1/2 in cervical swabs from the CSWs. The prevalence of HPV infection was 83.5% in 188 cervical swab specimens and the main high-risk HPV genotypes were HPV16, 18, 56, and 58. The principal low-risk HPV genotypes were HPV6 and 11. The prevalence of HSV1/2 DNA was 13.8% and HSV2 seroprevalence was 86.2%. These results suggest that high frequencies of HPV and HSV2 infection might contribute to the rapid spread of STD viruses in CSWs in Korea. Additionally, an understanding of why high-risk HPV genotypes are so prevalent could provide guidelines for prophylactic vaccine development in Korea.