<p>While emerging adulthood (ages 18-25) is marked by increased independence from parents, parental support remains a strong correlate of positive sexual health outcomes for heterosexual youth. With the emergence of pre-exposure prophylaxis (PrEP), few studies have examined the potential for parent-child sex communication and PrEP adoption among emerging adult men who have sex with men (MSM). We aimed to describe the extent to which parents/family characteristics play supportive roles in emerging adult MSM's current PrEP use. PrEP-indicated participants (N = 222) were recruited via social media to complete an online survey. Multivariable logistic regression assessed associations between emerging adult MSM's current PrEP use and comfort with parent-child sex communication, family social support, family outness, and family prioritization, adjusted for sociodemographic variables. Thirty percent of participants reported current PrEP use. Only 20% reported moderate/high comfort with parent sex communication, 80% reported any family sexual identity disclosure, 70% reported moderate/high family social support, and 70% ranked family as a high/very high priority. Our multivariable model demonstrated an association between comfort with parent-child sex communication with current PrEP use only (AOR= 1.55, 95% CI 1.04-2.32). Our findings support that parents of emerging adult MSM possess a critical potential to reduce their sons' risk of HIV and promote PrEP uptake. Interventions that facilitate parents' efficacy to foster affirming, non-judgmental environments and discussions about their child's sexual behaviors, attractions/relationships, and health (e.g., PrEP) may be impactful in reducing the high HIV incidence rate that burdens emerging adult MSM.</p>