Purpose <p>Physical activity benefits mental health, with emotional autobiographical memory and repetitive negative thinking (RNT) as potential mechanisms. This study expands upon prior laboratory studies by examining how physical activity is associated with emotional autobiographical memory and RNT in daily life, utilizing the experience sampling method (ESM).</p> Methods <p>A community sample (N = 112) was prompted four times daily for seven consecutive days to report their recent physical activity duration and intensity, RNT, recall of a recent personal event, and their current positive and negative mood states.</p> Results <p>Participants evaluated recalled events as more pleasant when they had been physically active for longer durations or at higher intensities in the preceding hours. No evidence was found for an association between physical activity and RNT. Confirming the mood-enhancing effect of physical activity, both activity duration and intensity were negatively associated with negative mood, and intensity positively with positive mood.</p> Conclusions <p>The results indicate that physical activity duration and intensity are positively associated with emotional autobiographical memory and mood states. This confirms the mental health benefits of physical activity using daily life data. Future research should further investigate emotional autobiographical memory as a mechanism underlying the protective effects of physical activity on mental health.</p>