OBJECTIVES: Translate into Brazilian Portuguese, cross cultural adaptation and assess the reliability and validity of the Systemic Lupus Erythematosus Quality of Life Questionnaire (SLEQOL). STUDY POPULATION: 107 SLE patients, answered the SLEQOL questionnaire. TRANSLATION: into Portuguese and cross-cultural adaptation was performed in accordance with studies on questionnaire translation methodology into other languages. RELIABILITY: Was analyzed using three interviews with different interviewers, two on the same day (interobserver) and the third within 14 days of the first assessment (intraobserver). VALIDITY: Validity was assessed by correlating clinical and quality of life parameters with the SLEQOL. STATISTICAL ANALYSIS: A descriptive analysis of the study sample. Reproducibility was assessed using an intraclass correlation coefficient (ICC). Internal consistency was assessed using Cronbach's alpha coefficient. To assess validity we used Pearson's correlation coefficient. Five percent was the level of significance adopted for all statistical tests. RESULTS: The SLEQOL was translated and culturally adapted. The main findings were: a 0.807 internal consistency correlation coefficient for all questions and domains. The inter and intraobserver correlation coefficients were 0.990 and 0.969 respectively. Validation showed good correlation with theSF-36 and poor correlation with lupus activity or damage indices. CONCLUSIONS: The quality of life parameter has been increasingly taken into account for chronic diseases. To date there are no tools to assess Quality of Life in Systemic Lupus Erythematosus (SLE) written in the Portuguese language. The questionnaire is valid and reliable for SLE patients in Brazil.