Background <p>Patients with psychiatric disorders often experience a reduced quality of life. To accurately assess their well-being, reliable and culturally appropriate tools are essential. The Mental Health Quality of Life (MHQoL) questionnaire, which has seven questions, is designed for this purpose. This study aimed to translate and evaluate the psychometric properties of the MHQoL tool among patients with psychiatric disorders at the psychiatric department of Baqiyatallah Hospital.</p> Methods <p>This study employed a methodological approach with a descriptive cross-sectional design. After obtaining written permission from the original developer and following the World Health Organization protocol, the Persian version of the questionnaire was administered to 300 psychiatric patients hospitalized in a psychiatric ward in Tehran from October 2022 to March 2023. Of the participants, 39% were female and 61% were male. The questionnaire’s face validity, content validity, and construct validity were subsequently evaluated. To determine reliability, Cronbach’s alpha coefficient and test-retest methods were used.</p> Results <p>Through exploratory factor analysis (<i>N</i> = 150) and confirmatory factor analysis (<i>N</i> = 150), one factor was extracted that explained 59.45% of the total observed variance. The model exhibited a good fit, with a GFI of 0.90, CFI of 0.97, IFI of 0.97, NFI of 0.95, PNFI of 0.64, RMSEA of 0.14, CMIN/DF of 3.5, and RMR of 0.049. The Persian version of the MHQoL tool demonstrated high reliability, with a Cronbach’s alpha of 0.876 and an intraclass correlation coefficient of 0.979.</p> Conclusions <p>The current study’s findings suggest that the Persian version of the MHQoL is valid and reliable for assessing the quality of life in Persian patients with psychiatric disorders.</p>