Sexually transmitted infections (STIs) continue to pose significant public health challenges in Korea, with syphilis, gonorrhea, chlamydia, , and herpes simplex virus (HSV) being the most prevalent. This review provides an updated overview of the epidemiology, diagnosis, and treatment of these significant STIs in Korea, highlighting recent trends and concerns. Syphilis incidence rates have fluctuated due to changes in surveillance systems. Starting in 2024, syphilis will be reclassified as a nationally notifiable infectious disease (category 2). Gonorrhea remains a concern due to increasing antibiotic resistance, including the emergence of extensively drug-resistant strains, underscoring the need for vigilant antimicrobial stewardship. Chlamydia continues to be the most commonly reported STI, although its incidence has declined during the COVID-19 pandemic. has gained attention as a significant STI with rising antibiotic resistance issues, necessitating updated treatment guidelines and consideration of resistance testing. HSV-2 remains a common cause of genital herpes, with steady incidence rates reported. Updated diagnostic methods, including nucleic acid amplification tests, and revised treatment guidelines are presented to effectively address these infections. The impact of the COVID-19 pandemic on other STIs within Korea remains unclear, necessitating further research. Changes in treatment guidelines, such as the recommendation of doxycycline as first-line therapy for chlamydia, reflect evolving evidence and resistance patterns. The importance of updated diagnostic tools, including resistance testing for , is emphasized to improve treatment outcomes. Continued efforts in education, prevention, and research are essential to manage and mitigate the impact of STIs on public health in Korea.