BACKGROUND: The human papillomavirus (HPV) vaccine is recommended for adolescent girls in many European countries, however there is huge variation in vaccine uptake. METHODS: A mixed methods systematic review to ascertain the level of HPV and HPV vaccine knowledge that exists among European adolescents. Two electronic databases, Ovid Medline and PsychInfo, were searched from origin to September 2014. Meta-analysis was performed for the two primary outcome measures ('have you heard of HPV?' and 'have you heard of the HPV vaccine?'), assessing for the correlation between gender and knowledge. This was supplemented with meta-synthesis for the remaining associations and secondary outcomes. RESULTS: 18 papers were included in the final review. Overall European adolescents had poor understanding of basic HPV and HPV vaccine knowledge. Meta-analysis identified that female adolescents are more likely to have heard of HPV (n=2598/5028 girls versus n=1033/3464 boys; OR 2.73, 95% CI 1.86-3.99) and the HPV vaccine (n=1154/2556 girls versus n=392/2074 boys; OR 5.64, 95% CI 2.43-13.07), compared to males. Age, higher education and a positive vaccination status were also associated with increased awareness. There was limited appreciation of more detailed HPV knowledge and uncertainty existed regarding the level of protection offered by the vaccine and the need for cervical screening post vaccination. CONCLUSIONS: The delivery of HPV education to European adolescents needs to be re-evaluated, since at present there appears to be significant deficiencies in their basic knowledge and understanding of the subject. Increasing HPV knowledge will empower adolescents to make informed choices regarding participation with HPV related cancer prevention health strategies.