The authors aimed to describe cell phone and Internet use and assess the correlation of Internet use for health care engagement purposes and HIV clinical outcomes among HIV-positive individuals. The authors conducted a national survey using online social media to examine cell phone and Internet use, self-reported HIV viral load (detectable vs. undetectable), and antiretroviral adherence rating (excellent vs. less than excellent). Participants (N = 1,494) were asked about their Internet use for health care engagement purposes (including e-mailing health care providers, refilling medications online, and making medical appointments online). Approximately 95% of participants accessed the Internet nearly daily or daily in the past month (mean hours on Internet use per day = 5.2) and 55.5% used the Internet for health care engagement purposes. Those who used the Internet for any health care engagement purposes had a 1.52-fold odds of reporting an undetectable viral load (p = .009) and a 1.49-fold odds of reporting excellent adherence (p = .001). Although Internet access and use were similar across racial/ethnic, educational, and socioeconomic groups, disparities existed with the use of the Internet for health care engagement purposes among racial/ethnic minorities, those with low to moderate financial stability, lower education, and history of incarceration. The authors' data reveal that among HIV-positive users of online social media, use of the Internet for health care engagement purposes is associated with better self-reported virologic and adherence outcomes.