Few research studies have examined the predictors of mental ill health in esports. This study addresses the gap by investigating the prevalence and relationships of mental ill health in a professional first-person shooter sample. An online survey was disseminated to professional first-person shooter athletes (n = 72). The survey included measures of stressors resulting from professionally competing in esports (competitive, organisational, personal), sleep quality, burnout, as well as outcome measures of mental ill health. We found that 60% of our sample had experienced symptoms of psychological distress (Distress Screener), 78.7% experienced psychological signs of anxiety or depression (GHQ-12), and 23.6% experienced moderately severe to severe symptoms of depression (PHQ-9), all in the previous four weeks. Correlation analyses examined these relationships. We found that competitive and personal stressors significantly and positively associated with the Distress Screener, and personal stressors significantly and positively associated with the PHQ-9. We also found burnout subscales of reduced sense of accomplishment and emotion and physical exhaustion and the sleep subscales of disturbance and daytime dysfunction significantly and positively associated to all outcome measures of mental ill health. We hope our findings can inform the development of evidencebased interventions designed to target specific aspects of stress, sleep, and burnout to improve the mental health of those who compete professionally in esports.