Abstract: Across two studies, we theorize and empirically investigate passion as a moderator of the negative affective consequences of fear of failure in early-stage entrepreneurship. We test our hypotheses in two field studies of naturally occurring affective events—namely, pitching competitions—and we complement self-reported measures of negative affect with physio-psychological measures obtained from analyzing entrepreneurs’ facial expressions. The results confirm that in failure-relevant situations, dispositional fear of failure may lead to higher negative affect depending on the dualistic regulatory effect of passion—harmonious passion dampens the influence of fear of failure on negative affect (Studies 1 and 2), while obsessive passion magnifies this effect in Study 1 but dampens it in Study 2, thus showing mixed evidence. Our work is one of the first to investigate how early-stage entrepreneurs experience negative affect during typical entrepreneurial events as a result of their dispositional traits and their type and level of passion.