Purpose Brands have increasingly used self-mockery in advertisements. Although previous insights from the social science literature assert that self-mockery is an effective strategy to boost brand closeness, the paper aims to show a more contigent view of self-mockery efficiency in an advertising context. Design/methodology/approach Two experiments were conducted. Findings This study shows that self-mockery helps build brand purchase intention through brand closeness only when self-mockery is based on a weak negative claim rather than a strong negative claim and that this influence occurs only for consumers with prior positive brand attitudes. Practical implications Marketing managers should consider self-mockery as a valuable brand-building strategy, especially if the main goal of the brand is to develop brand closeness among consumers with prior positive brand attitudes. Originality/value First, the current research is the first to provide empirical support for the mediating role of brand closeness to explain how self-mockery influences brand purchase intention. Second, this study qualify previous results and the popular idea that self-mockery may systematically help build brand closeness. This study demonstrates that this effect is conditional on the strength of the negative attribute claim disclosed and consumers’ prior brand attitudes.