This article describes the psychometric properties of the Brazilian version of the Social Behaviour Schedule – SBS, developed to provide global assessments of functional living skills of chronically mentally ill individuals. Núcleo de Pesquisa do Instituto Municipal de Assistência à Saúde Juliano Moreira (IMASJM), RJ, has conducted the questionnaires translation and adaptation and the data collection took place in the health care units of IMASJM. Núcleo de Ensino e Saúde Coletiva (NESC) da UFRJ has conducted the analysis assessing the scale psychometric properties. The scale was submitted to a backtranslation, an evaluation by an expert committee and a pilot study in other to implement its adaptation to the Brazilian context. The results showed good psychometric properties of reliability and validity, in terms of the internal consistency of the scale, construct validity of the scale and its discriminant validity. Future studies should investigate inter-rater reability and inter-informant reliability. The SBSBR is an important instrument to evaluate mental health programs for severe mentally ill patients.