Despite the increased use of social media and text messaging among adolescents, it is unclear how effective education transmitted via these mechanisms is for reducing sexual risk behavior. Accordingly, we conducted a systematic review of the literature to examine the effectiveness of social media and text messaging interventions designed to increase sexually transmitted disease (STD) knowledge, increase screening/testing, decrease risky sexual behaviors, and reduce the incidence of STDs among young adults aged 15 through 24 years. Eleven studies met our inclusion criteria. Most of the included studies used a control group to explore intervention effects and included both young men and women. Sample sizes ranged from 32 to 7606 participants, and follow-up periods ranged between 4 weeks and 12 months. These studies provide preliminary evidence indicating that social media and text messaging can increase knowledge regarding the prevention of STDs. These interventions may also affect behavior, such as screening/testing for STDs, sexual risk behaviors, and STD acquisition, but the evidence for effect is weak. Many of these studies had several limitations that future research should address, including a reliance on self-reported data, small sample sizes, poor retention, low generalizability, and low analytic rigor. Additional research is needed to determine the most effective and engaging approaches for young men and women.