Background: Findings from existing research exploring whether positive social exchanges can help to offset (or 'buffer' against) the harmful effects of negative social exchanges on mental health have been inconsistent. This could be because the existing research is characterized by different approaches to studying various contexts of 'cross-domain' and 'within-domain' buffering, and/or because the nature of buffering effects varies according to sociodemographic characteristics that underlie different aspects of social network structure and function. Objective: The purpose of this study was to examine whether the buffering effects of global perceptions of positive exchanges on the link between global negative exchanges and mental health varied as a function of age and gender. Method: We used a series of regressions in a sample of 556 Australian older adults (ages 55-94) to test for three-way interactions among gender, positive social exchanges, and negative social exchanges, as well as age and positive and negative social exchanges, in predicting mental health, controlling for years of education, partner status, and physical functioning. Results: We found that positive exchanges buffered against negative exchanges for younger old adults, but not for older old adults, and for women, but not for men. Conclusions: Our findings are interpreted in light of research on individual differences in coping responses and interpersonal goals among late middle-aged and older adults. Our findings are in line with gerontological theories (e.g. socioemotional selectivity theory), and imply that an intervention aimed at using positive social exchanges as a means of coping with negative social exchanges might be more successful among particular populations (i.e. women, 'younger' old adults).