The effects of emotional processing on stress response trajectories may depend on the nature of processing, as evaluative rumination about emotions can prolong distress. In contrast, observing negative emotions in an accepting manner may promote efficient recovery from stressful situations. The present study examined the effect of acceptance-oriented versus evaluative emotional processing on cardiovascular habituation and recovery. Across two experimental sessions, 81 participants were randomly assigned to write about an ongoing stressful experience while either (1) evaluating the appropriateness of their emotional response (EVAL), (2) attending to their emotions in an accepting way (ACC), or (3) describing the objective details of the experience (CTL). Heart rate was assessed continuously throughout baseline, writing, and recovery. Results suggest that writing about emotions in an evaluative way leads to less efficient heart rate habituation and recovery than processing emotions in an accepting manner. These findings highlight a potential mechanism of mindfulness- and acceptance-based interventions' effects on health outcomes and further suggest that habitually evaluating the appropriateness of one's emotional responses rather than accepting them as they unfold may have consequences for cardiovascular health.