Women with polycystic ovarian syndrome (PCOS) have been found to suffer from fertility problems and mood dysfunction. To control for any effect of fertility problems, the present study compared mood dysfunction in women with PCOS to non-PCOS women with fertility problems. Seventy-six women with PCOS and 49 subfertile controls reported their anxiety, depression and aggression levels, and the relationship between mood and testosterone (T) was assessed. Controlling for age and BMI using MANCOVA, women with PCOS were significantly more neurotic (had difficulty coping with stress) than controls, had more anger symptoms, were significantly more likely to withhold feelings of anger and had more quality of life problems related to the symptoms of their condition (acne, hirsutism, menstrual problems and emotions). In a subgroup of 30 women matched on age, BMI and ethnicity, it was found that women with PCOS were significantly more anxious and depressed than controls. T was not generally correlated with mood states. This is the first study to identify problems with neuroticism and withholding anger in women with PCOS. These mood problems appear to be mainly attributable to PCOS symptoms, though other factors, such as hypoglycaemia, cannot be ruled out.