The difference between quadrivalent and bivalent is mainly in the prevention of different types of HPV viruses and different preventable diseases. The appropriate age for vaccination is 9-45 years old. Nine-valent mainly targets HPV6, 11, 16, 18, 31, 45, 52 and 58 virus subtypes; four-valent mainly targets lower-risk viruses HPV6 and 11, and high-risk viruses HPV16 and 18; two-valent mainly targets high-risk viruses HPV16 and 18. Nine-valent can prevent 90% of cervical cancer, vaginal cancer, vulvar cancer, anal cancer, precancerous lesions and other atypical lesions caused by HPV; four-valent can prevent cervical cancer, genital warts and so on; two-valent can mainly prevent cervical cancer. HPV vaccine is a prophylactic vaccine, which cannot treat infected HPV and related diseases, prevent all HPV types of infections, or stop HPV infections from progressing to disease progression. Therefore, regular cervical cancer screening is still needed after HPV vaccination.