The interval between the three doses of HPV 9 vaccine is 0 month, 2nd month and 6th month. The HPV 9-valent vaccine needs to be completed in three doses, after the first dose, the second dose in the second month, and the third dose in the sixth month after the first dose. It is best to complete all three doses within six months to avoid compromising the effectiveness of the vaccine. HPV refers to human papillomavirus, which is one of the most important causes of cervical cancer. HPV vaccine can effectively prevent diseases caused by HPV infection, especially cervical cancer in women, as well as condyloma acuminatum, vulvar cancer, anal cancer, etc. The age of HPV vaccine is limited to 9-26 years old, and it is recommended that women of the appropriate age should receive the vaccination in time. It should be noted that the vaccine should be avoided during menstruation, pregnancy, acute fever, allergy to the vaccine is prohibited, the specific circumstances can be consulted with the local community or hospitals, and follow the instructions of the doctor, in order to avoid causing adverse reactions.