Psychological distress in rheumatoid arthritis (RA) is associated with adverse clinical outcomes, and appears highly related to patients' illness perceptions. This study aimed to investigate the association between illness perceptions, psychological distress, positive outlook and physical outcomes in RA. Two hundred and thirty patients aged >18 years and prescribed at least one disease-modifying anti-rheumatic drug (DMARD) were recruited from outpatient clinics across Hertfordshire (England). Patients completed a questionnaire that assessed psychological distress and positive outlook (depression, anxiety and positive outlook scale), illness perceptions (IPQ-R) and functional disability (health assessment questionnaire). Information regarding prescribed medication and disease activity [disease activity score (DAS28)] was collected from medical notes. Psychological distress, but not positive outlook, was associated with functional disability and DAS28. After controlling for sex, age and DAS28, perceptions of greater symptomatology (identity) and lesser understanding of RA (coherence) were significantly associated with increased psychological distress. Perceptions of greater treatment control were associated with greater positive outlook, but only for those with low DAS28. Coherence was also associated with positive outlook. These findings indicate that illness perceptions may influence psychological distress and positive outlook in RA patients, and may therefore be a useful basis for future psychological interventions.