In Kenya, a nine-year follow-up of a cohort of 180 adolescents living with HIV who received three doses of the quadrivalent HPV vaccine at ages 9–14 found sustained vaccine-specific protection, with zero persistent infections detected for HPV types 11, 16, or 18 among 151 evaluable participants. Only two participants (1.3%) had any vaccine-genotype persistent infection, both involving low-risk HPV-6, in a population where over 99% were on antiretroviral therapy and 65% had suppressed HIV viral load at re-enrolment. By contrast, persistent non-vaccine genotype infection remained high at 30.5%, and any non-vaccine genotype infection was detected in 41.9% of participants, underscoring residual risk from genotypes not covered by the quadrivalent vaccine. These findings support the long-term durability of quadrivalent HPV vaccination in adolescents living with HIV and reinforce the programmatic case for prioritising this high-risk population in vaccination strategies, while also highlighting the potential added benefit of higher-valency vaccines.