(1) Background: Hungarys's estimated cervical cancer mortality was 6.9/100,000 in 2012, above the average of the EU27 countries (3.7/100,000) in the same year. Since 2014, the bivalent HPV vaccine has been offered to schoolgirls aged 12-13. (2) Methods: We conducted a cross-sectional study among 1022 high school seniors (492 girls, 530 boys) in 19 randomly selected schools in Budapest. Our anonymous questionnaire contained 54 items: basic socio-demographic data, knowledge about HPV infection/cervical cancer and HPV vaccination. (3) Results: 54.9% knew that HPV caused cervical cancer, and 52.1% identified HPV as an STD. Knowledge of risk factors such as promiscuity (46.9%) and early sexual activity (15.6%) was low, but higher than that of further HPV-induced diseases: genital warts (in females 9.9%, in males 9%), anal cancer (in females 2.2%, in males 1.9%), penile cancer (9.4%), and vulvar cancer (7.8%). A percentage of 14.6% feared getting infected, and 35.7% supported compulsory HPV vaccination. A percentage of 51.2% would have their future children vaccinated-significantly more girls than boys. (4) Conclusion: Our results support the findings of previous studies about young adults' HPV-related knowledge, which was poor, especially regarding pathologies in men. Despite the low level of awareness, the students' attitude was mostly positive when asked about vaccinating their future children.