IntroductionWorld Health Organization (WHO) has developed HIV specific quality of life tool called World Health Organization Quality of Life brief questionnaire in HIV population (WHOQOL-HIV BREF) for assessing the quality of life of people living with HIV/AIDS (PLWHA). Despite its sound validity and reliability from several studies, the developers recommend it to be validated in different cultures to assess its psychometric properties before its adoption. The study aimed at evaluating the validity and reliability of the Kiswahili version of the WHOQOL-HIV BREF questionnaire in Tanzania among people living with HIV/AIDS.Methodsa cross-sectional study with 103 participants recruited via systematic random sampling. The internal consistency of the questionnaire was assessed by the Cronbach alpha coefficient. Validity of the WHOQOL-HIV BREF was assessed through analysis of construct, concurrent, convergent and discriminant validity. The model performance was assessed by exploratory and confirmatory factor analysis.Resultsthe mean age of the participants was 40.5 ± 9.702 years. The internal consistency of the items of the Kiswahili version of WHOQOL-HIV BREF shows Cronbach's alpha values of 0.89-0.90 (p < 0.001). Analysis of test-retest reliability showed a statistically significant Intra-class correlation (ICC) of 0.91 - 0.92 (p < 0.001). The spiritual and physical domains were highly discriminated from the rest of the domains (Psychological, Environmental, Social and Independent domain).ConclusionKiswahili WHOQOL-HIV BREF tool was found to have good validity and reliability among Tanzanian people living with HIV/AIDS. These findings provide support for the use of this tool in assessing the quality of life in Tanzania.