In recent years, several investigations of the medical clowning profession have appeared in the literature. However, few studies have focused on factors associated with turnover among medical clowns early in their careers. The current study examined whether individual differences in humor disposition predicted turnover behavior. Participants were 111 medical clowns in a three-phase longitudinal study. Humor disposition was measured in the first week of their training, clowns' job satisfaction two months later, and turnover six months after that. Results showed that humor appreciation decreased actual turnover through the mediating role of job satisfaction, whereas individual differences in humor creation directly decreased turnover. In addition, previous traumatic experiences moderated the associations between humor appreciation and turnover. Overall, our research findings support the notion that humor disposition can help predict which clowns remain in the hospital.