A 30-day diary study examined the relations among trait self-esteem, negative romantic relationship interactions, and alcohol consumption. Multilevel analyses revealed that people with low trait self-esteem (compared with people with high trait self-esteem) drank more on days when they experienced more negative relationship interactions with their romantic partners. In addition, daily increases in state self-esteem buffered people with low trait self-esteem from the desire to drink in response to negative romantic relationship interactions. In contrast, participants with high and low self-esteem both decreased their drinking in response to negative non-romantic relationship events, but people with low self-esteem decreased their drinking less. These findings suggest that people with low trait self-esteem may drink as a way to regulate unfulfilled needs for acceptance.