Objective[|]The study aimed to determine sleep quality and factors affecting it in patients with chronic psychological disorders.[¤]Materials and Methods[|]The research was conducted at Gevher Nesibe Medical Faculty Hospital of Erciyes University between March 10th, 2009 and April 10th, 2009. In total, 132 patients with psychiatric disorders were included, and all the patients were asked to fill the Pittsburgh Sleep Quality Index (PSQI) and Personal Information Forms.[¤]Results[|]According to the data obtained, the mean scores of PSQI were as follows: sleep duration, 1.17±1.09 h; sleep efficacy, 1.23±0.97; daytime dysfunction, 1.40±1.01; sleep disorder, 1.16±0.83; sleep latency, 2.80±1.58; sleeping pills, 1.35±0.76; and global PSQI, 9.13±2.37. In total, 93.2% of the patients were found to have a bad sleeping quality. As the global PSQI scores increased, sleeping time, sleeping pill use, sleeping quality, sleeping activity, sleep latency, and daytime dysfunction scores also increased (p<0.05). In addition, there was a positive correlation among them. The correlation between the global PSQI scores and marital status and between the place of residence and occupational-professional status was found to be significant (p<0.05).[¤]Conclusion[|]As patients with chronic psychiatric disorders have frequent sleep problems, planning interventions for the sleep problems of patients can be recommended.[¤]