 The last ten years sexually transmitted infections STI have substantially increased among adolescents. STI can lead to individual suffering and have a negative effect on the future reproductive health and also increase the need for health care, thus it is important to reduce the number of STIs. HPV vaccination is included in the school-based vaccination program since 2012, a catch-up vaccination is offered to older girls and young women aged 13-25. School nurses have a key role regarding information about HPV and HPV vaccine, and the school-based vaccination program has a substantial higher coverage rate. Knowledge is an important factor associated with attitude to preventive methods against HPV. In previous studies the results indicate that young people have low awareness of HPV and the HPV vaccine. Interventions can decrease sexual risk taking and influence the intention to receive HPV vaccination and increase the use of condom. 