Suggested citation: Bordignon S, Aparício MJ, Bertoletti J, Trentini CM. Personality characteristics and bariatric surgery outcomes: a systematic review. Trends Psychiatry Psychother. 2017;39(2):124-134. http://dx.doi.org/10.1590/2237-6089-2016 Abstract Introduction: Numerous studies have focused on psychological assessment of bariatric surgery candidates, aiming to identify which psychological variables, including personality characteristics, are related to successful surgical prognosis. Objective: To analyze, by means of a systematic literature review, longitudinal studies that investigated personality traits and disorders as possible predictors of outcomes in bariatric surgery. Method: PsycInfo, PubMed, and Scopus databases were searched for studies published between 2005 and 2015, using the keywords "bariatric" AND "personality." Quantitative longitudinal studies in English, Portuguese, or Spanish were selected for review if they assessed personality as an outcome predictor of BS in people aged 18 years or older. Results: Sixteen articles were analyzed. The results of this review suggest that externalizing dysfunctions might be associated with less weight reduction, while internalizing dysfunctions appear to be associated with somatic concerns and psychological distress. The persistence dimension (of temperament in Cloninger's model) was positively associated with greater weight loss, while neuroticism (Five Factor Model) and the occurrence of personality disorders were not predictive of weight loss. Furthermore, the results indicate a tendency towards a reduction in personality disorders and neuroticism scores, and an increase in extroversion scores, after BS. Conclusions: Assessment of personality characteristics, whether to identify their predictive power or to detect changes during the BS process, is important since it can provide grounds for estimating surgical prognosis and for development of interventions targeting this population.