OBJECTIVES: The aim of this study was to determine the reliability and validity of the Functional Outcomes of Sleep Questionnaire (FOSQ) for the Turkish population. METHODS: A total of 200 university students participated. A total of 52% of them were men, 48% of them were women. A total of 43% of them lived in the dormitory and 57% of them lived at the apartments. Data were collected with a sociodemographic form, FOSQ, and SF-36. Cronbach's Alfa was used to assess reliability and factor analysis to assess dimensionality. The SF-36 was used for concurrent validity. RESULTS: The internal consistency coefficient (Cronbach's alpha) of FOSQ was 0.90. Factor analysis of the scale revealed that it was composed of three factors with Eigenvalues >2.0, accounting for 57.6% of the total variance. All items of the Turkish FOSQ had a factor load ranging from 0.413 to 0.731. There was a strong relationship between Functional Outcomes of Sleep Questionnaire, and SF-36. CONCLUSIONS: The culturally adapted Functional Outcomes of Sleep Questionnaire had good validity and reliability, making it a potentially useful outcome measure in the evaluation of insomnia patients in Turkey.