To explore the relationship between potential psychological risk factors and injury risk in circus artists. Historical cohort study. Cirque du Soleil training programme. Forty-seven circus artists training to become Cirque du Soleil artists. Artists completed the validated REST-Q questionnaire (19 domains) during their first 2 weeks of training. Injury risk ratio. Of the five a priori exposures of interest, injury, emotional exhaustion, self-efficacy and fatigue were associated with an increase in injury risk (risk ratios between 1.8 and 2.8), but Conflicts/Pressure was not (risk ratio=0.8). Of the several specific psychological aspects that are considered risk factors for injury, low self-efficacy had the strongest relationship. Most of the strong psychological risk factors for injuries previously identified in athletes also appear to be risk factors in circus artists.