The difference between the 2-valent, 4-valent and 9-valent cervical cancer vaccines is mainly that they prevent different HPV types and are applied to different age groups. 2-valent cervical cancer vaccine can prevent 16 and 18 HPV infections, and the appropriate age is 9-25 years old. 4-valent cervical cancer vaccine can prevent 6, 11, 16 and 18 HPV infections, and the appropriate age is 20-45 years old. 9-valent cervical cancer vaccine can prevent 6, 11, 16, 18, 31, 33, 45, 52 and 58 HPV infections, and the appropriate age is 16-26 years old. The 9-valent cervical cancer vaccine can prevent 6, 11, 16, 18, 31, 33, 45, 52 and 58 HPV infections, and the appropriate age is 16-26 years old. However, no matter which cervical cancer vaccine can prevent all high-risk HPV infections, so even if you have received the cervical vaccine, you still need to have regular cervical cancer screenings.