The Job Demands-Resources (JD-R) model was constructed to explain the antecedents, consequences, and relationships of burnout, and has provided evidence that personal resources moderate and weaken the relationship between job demands and burnout. Although much of the personal resource literature focuses on personality traits like optimism and self-esteem, the moderating effect of trait mindfulness on the relationship between job demands and job burnout has yet to be examined. The study hypothesized that mindfulness moderates the relationship between four job demands (role ambiguity, interpersonal conflict, work-life conflict, and cognitive demands) and three dimensions of burnout, such that those with higher levels of mindfulness experience less burnout when job demands are high. A total of 126 knowledge workers in the technology industry participated in the study by filling out a survey using Qualtrics. Consistent with the hypothesis, mindfulness moderated the relationship between cognitive demands and exhaustion, such that the relationship between cognitive demands and exhaustion was weakened for individuals with high mindfulness. Contrary to the hypothesis, mindfulness moderated the relationship between interpersonal demands and exhaustion such that relationship between interpersonal demands and exhaustion was stronger for individuals with high mindfulness. Thus, mindfulness does not always benefit individuals when subjected to high job demands, and organizations should consider their environment before hiring for mindful individuals.