Gardasil Vaccine is a vaccine used to prevent cervical cancer associate with human papilloma virus (HPV) in women. it works by initiating a mild infection to stimulate the body's immune system to produce antibodies to protect against any future infections. A quasi-experimental study was conducted to assess the effectiveness of information booklet on knowledge regarding Gardasil 9 vaccine for the prevention of cervical cancer among adolescent girls in selected inter colleges, at Kanpur, UP. A total 60 samples were collected by using Non-Probability Purposive Sampling Technique through self-structured knowledge questionnaire, the data collected and analysed and descriptive on inferential statistics. The results of the study showed that post-test mean score(21.5)was high when compared to the pre-test mean score at (13.91). The obtained “t” value 17.44 was greater than t-value (2.00) & df 59 which was p<0.05 level which shows significance differences between pre-test and post-test level of knowledge hence the formulated research Hypothesis H1 was accepted. The test revealed that there was no significant association of knowledge with selected demographic variables such as Source of information so there were significant with association with, Age group, Religion, Mother qualification, Habits, Age of menarche, Health access, Type of family, Family monthly income,Previousknowledge,buttherewasnosignificantwithotherselected demographic variables, were found no significant at <0.05 level of significance. The study concluded that Information Book let was effective and improve knowledge regarding Gardasil 9 for the prevention of the cervical cancer among adolescent girls.