OBJECTIVE The consumption of alcohol mixed with energy drinks (AmED) is popular on college campuses in the United States. Limited research suggests that energy drink consumption lessens subjective intoxication in persons who also have consumed alcohol. This study examines the relationship between energy drink use, high-risk drinking behavior, and alcohol-related consequences. METHODS In Fall 2006, a Web-based survey was conducted in a stratified random sample of 4,271 college students from 10 universities in North Carolina. RESULTS A total of 697 students (24% of past 30-day drinkers) reported consuming AmED in the past 30 days. Students who were male, white, intramural athletes, fraternity or sorority members or pledges, and younger were significantly more likely to consume AmED. In multivariable analyses, consumption of AmED was associated with increased heavy episodic drinking (6.4 days vs. 3.4 days on average; p < 0.001) and twice as many episodes of weekly drunkenness (1.4 days/week vs. 0.73 days/week; p < 0.001). Students who reported consuming AmED had significantly higher prevalence of alcohol-related consequences, including being taken advantage of sexually, taking advantage of another sexually, riding with an intoxicated driver, being physically hurt or injured, and requiring medical treatment (p < 0.05). The effect of consuming AmED on driving while intoxicated depended on a student's reported typical alcohol consumption (interaction p = 0.027). CONCLUSIONS Almost one-quarter of college student current drinkers reported mixing alcohol with energy drinks. These students are at increased risk for alcohol-related consequences, even after adjusting for the amount of alcohol consumed. Further research is necessary to understand this association and to develop targeted interventions to reduce risk.