Adolescent males who have sex with males (AMSMs) account for high numbers of new HIV diagnoses. To date, surveillance data have been limited to diagnosed cases of HIV, resulting in an underestimation of risk and burden among AMSMs unwilling or unable to access HIV testing. This study identified facilitators and barriers to AMSMs' participation in future surveillance studies involving HIV testing. AMSMs (n = 198) aged 14 to 17 years participated. The majority identified as non-Hispanic White or Latinx, had a least 1 male sex partner, and self-reported HIV negative. Participants read an online survey beginning with a vignette describing a hypothetical HIV surveillance study requiring HIV testing. They then completed questions assessing likelihood to participate, perceived research benefits and risks, attitudes toward HIV risk, prior HIV health services, and parental awareness of sexual orientation. Approximately 40% indicated strong willingness to participate. Willingness was positively related to perceived HIV risk, free access to HIV testing, counseling and referral if testing positive, confidentiality protections, and lack of access to a trusted physician. Having to tell others if one tested positive for HIV and requirements for guardian permission were significant participation barriers. Inclusion of HIV testing in surveillance studies is essential for accurate estimation of HIV incidence and prevalence among AMSMs. Successful recruitment of sexual minority youth into sexual health surveillance research will require procedures tailored to youth's health care needs and concerns, including adequate HIV counseling, referral to treatment if seropositive, and attention to concerns regarding guardian permission. (PsycINFO Database Record (c) 2019 APA, all rights reserved).