The aim of the present study was to identify the sexual behavior, attitudes, beliefs, and knowledge on sexually transmitted infections (STIs) focused on human papilloma virus (HPV) in the Greek adolescent population. The participants were 4547 adolescents, a representative sample for Greek territory with a mean age of 17 years. After written permission from Greek ministry of education each student completed a questionnaire with 36 questions. The fields covered were demographic characteristics, sexual life data, and basic knowledge on HPV. In the present study, 43% and 75% of the participants knew about HPV or cervical cancer, while more than 6 out of 10 did not know the association between the 2. More than 60% of the participants could not answer correctly neither about HPV infection and cervical cancer frequency in sexually active women, nor about protection methods against HPV and cervical cancer. This study shows that the low vaccination coverage of the Greek population may be due to lack of information and awareness of the adolescents and their parents. It is our duty to increase our efforts in order to better educate the population and vaccinate the population as early as possible in their reproductive years.