Binge-eating disorder (BED) is associated with overweight/obesity, physical inactivity, and disturbances in affective functioning. While research suggests that physical activity (PA) may have beneficial effects on BED symptoms, little is known about the daily correlates of PA. As a first step in understanding the processes linking PA and binge eating, this study examined associations between PA (i.e., self-reported time engaged in moderate-to-vigorous PA), affective functioning (i.e., positive and negative affect, body satisfaction, emotion regulation), and eating-related cognitions and behaviors (i.e., craving, overeating, loss of control eating) measured via ecological momentary assessment (EMA). Adults with BED ( = 91) completed a seven-day EMA protocol during which they completed repeated measures of these variables. Results indicated individuals who reported greater time engaged in PA over the EMA protocol evidenced higher positive affect and body satisfaction, and lower overeating (between-subjects effects). No significant within-subjects effects were observed. Findings demonstrate that individual differences in PA levels were related to more adaptive affective functioning and eating regulation in daily life. Results highlight the relevance of PA in BED, and the need for future studies to identify the timescale of these relationships using objective measurements of PA.