Arousal has been found to increase learners' attentional resources. In contrast, seductive details (interesting but learning-irrelevant information) are considered to distract attention away from relevant information and, thus, hinder learning. However, a possibly moderating role of arousal on the seductive detail effect has not been examined yet. In this study, arousal variations were induced via audio files of false heartbeats. In consequence, 100 participants were randomly assigned to a 2 (with or without seductive details) x 2 (lower vs. higher false heart rates) between-subjects design. Data on learning performance, cognitive load, motivation, heartbeat frequency, and electro-dermal activity were collected. Results show learning-inhibiting effects for seductive details and learning-enhancing effects for higher false heart rates. Cognitive processes mediate both effects. However, the detrimental effect of seductive details was not present when heart rate was higher. Results indicate that the seductive detail effect is moderated by a learner's state of arousal.