In this study, we investigated the relationship between work–family conflict and job burnout as well as the potential mediation/moderation effects of psychological capital. Participants were 357 university teachers who completed a questionnaire packet containing a work–family conflict scale, psychological capital questionnaire, and Maslach Burnout Inventory–General survey. According to the results, work–family conflict and psychological capital were both significantly correlated with job burnout. In addition, psychological capital cannot mediate—but can moderate—the relationship between work–family conflict and job burnout. Taken together, our findings shed light on the psychological capital underlying the association of work–family conflict and job burnout.