Objective: The aims of this field research are to investigate the prevalence rates, psychiatric comorbidity, and quality of life in patients with bipolar disorders (BD) in Sivas province. Methods: One thousand and four hundred-six people from 510 houses that represent of Sivas province constituted the sample of this research. Sociodemographic Information Form, Structural Clinical Interview for DSM-IV Axis I Disorders, Clinical Version (SCID-I), Structural Clinical Interview for DSM-III-R Axis II Personality (SCID-II), and 36-Item Short-Form Quality of Life (SF-36) were applied to the sample. Data are evaluated using chi-square test and Mann Whitney U test. Findings: The lifetime prevalence rate of BD was 0.71%, for BD-I was 0.43%, for BD-II and cyclothymic disorder was 0.14%. According to SCID-I, anxiety disorders (psychiatric comorbidity) was found to be 30% of patients, and personality disorder was found to be 50% according to SCID-II. The points of physical role difficulties, general health, social functionality, and emotional role difficulties subscales of SF-36 were found significantly lower in patient group than control group. Discussion: The prevalence and psychiatric comorbidity was similar to other countries. BD has been affected quality of life of patients as negative. It may given useful knowledge that a field research with represented Turkey. [Anadolu Psikiyatri Derg 2015; 16(2.000): 85-94]