Abstract: This study examined the effects of chief executive officers’ (CEOs) self-disclosure on consumer–brand relationships and the moderating role of brand relationship norms. To test the proposed hypotheses, a 2 × 2 factorial design was implemented with self-disclosure (high vs. low) and relationship norms (exchange v. communal) as the between-subjects factors. The results showed the interplay between the level of CEOs’ self-disclosure on Instagram and the type of relationship norms between consumers and brands and their effects on consumers’ attitudinal and behavioral responses. For participants primed with the communal norm, high CEO self-disclosure induced more positive attitudes toward the CEO and the brand as well as higher consumer intentions for self-disclosure, than the low CEO self-disclosure; these results were reversed for participants in the exchange norm condition. This study advances the theoretical understanding of brands’ social media engagement using CEOs and provides practical implications.