Background: Although numerous studies have reported an association between sleep quality and mental health, few have focused on this association exclusively in early adolescence. Targeting this age group is vital as many mental illnesses first emerge during adolescence and remain a significant burden throughout life. Method: In the current study n = 60 participants aged 12 years completed the Pittsburgh Sleep Quality Index (PSQI) and Kessler Psychological Distress Scale (K10). Results: Consistent with previous findings, bivariate correlations revealed significant positive linear relationships between K10 total score and (i) PSQI total score; (ii) sleep quality; (iii) daytime dysfunction; and (iv) sleep disturbance. However, contrary to previous findings, there was no significant correlation between K10 scores and sleep duration. Conclusion: The association between sleep quality and psychological distress in early adolescents provides some important clues about the role that sleep may play in predicting the onset of anxiety and depressive disorders. Longitudinal studies should be undertaken to investigate age-related changes in sleep and psychological distress.