It is important to clarify the difference between the nine-valent cervical cancer vaccine and the quadrivalent cervical cancer vaccine. The quadrivalent cervical cancer vaccine mainly targets four types of HPV infections, namely 6, 11, 16 and 18, while the nine-valent cervical cancer vaccine can target nine types of HPV infections, namely 6, 11, 16, 18, 45, 52, 58, 31 and 33, so the nine-valent vaccine can prevent more types of HPV infections than the quadrivalent vaccine. Therefore, the prevention effect of the nine-valent vaccine is definitely better than that of the quadrivalent vaccine. However, the current age for the nine-valent vaccine for cervical cancer is 16-26 years old in mainland China, so once you are over the age, you cannot receive the nine-valent vaccine. The recommended age for quadrivalent vaccine is 20-45 years old. If you meet the age requirement, you can receive both quadrivalent and nine-valent vaccines, and the nine-valent vaccine is definitely better than the quadrivalent vaccine. If you are over the age of vaccination, you can only receive the quadrivalent vaccine. The conditions for obtaining the nine-valent vaccine are relatively strict, and it is very difficult to buy the nine-valent vaccine, so if the nine-valent vaccine is not available or can be received, the quadrivalent vaccine can be given first for prevention.