This course will systematically introduce the introduction to (1) necessity, purpose and significance of sexual and reproductive health; (2) principles of sexual mental health and reproductive health education; (3) introduction to immunology; (4) introduction of sexually transmitted disease and explain in detail the different types of sexually transmitted diseases, including biology of pathogens, clinical symptoms and pathology, clinical treatment and preventive protection measures, and the remaining problems and challenges. We will divide major pathogens into viruses, bacteria, fungi, and protozoa. Pathogens include HIV virus, HPV virus, HSV virus, Chlamydia, Neisseria, Mycoplasma, Syphilis, Candida albicans, Trichomonas vaginalis, etc.