Heightened impulsivity is a risk factor for problematic alcohol use among emerging adults. However, recent literature suggests that impulsivity is comprised of several facets that have shown differential relationships with alcohol use versus alcohol-related problems. Previous reviews have noted the bivariate associations between facets and alcohol use outcomes, but have not honed in on which facets may explain more variance in alcohol-related outcomes once other facets are accounted for. As such, certain facets may be more relevant than others in predicting alcohol-related harms among emerging adults. Consequently, the purpose of this review was to support the validity of discrete impulsivity facets and to identify specific facets that may pose most risk for alcohol-related harms. Based on previous research, the present review focused on five facets from the self-report impulsivity literature (i.e., sensation seeking, negative urgency, positive urgency, premeditation, and perseverance) and two facets from the behavioral impulsivity literature (i.e., impulsive action and impulsive choice). Conceptual and empirical evidence were provided to support the distinction of these self-report and behavioral facets, and literature comparing each of their relative contributions to alcohol use and alcohol-related problems, while controlling for the influence of other facets, is summarized. Overall, it is suggested that among emerging adults, sensation seeking is the strongest predictor of alcohol use whereas positive and negative urgency are the strongest predictors of alcohol-related problems. Implications and directions for future research were proposed.