Marketers increasingly employ generative AI technologies in content creation. However, whether and how disclosing AI authorship may affect consumers’ brand perceptions remains underexplored. This thesis investigates the impact of disclosing whether marketing content was AI-generated or human-written, specifically on consumer perceptions of the brand’s warmth and competence. In general, I hypothesize that brand perceptions will be more negative when content (e.g., a blog post) is disclosed to be authored by AI compared to by a human. However, I theorize the effect may depend on whether the content is informational or narrative in nature, such that the negative impact of AI disclosure is expected to be greater for narrative content than informational content. These hypotheses were examined across two experiments. The results of Study 1 revealed that human-written content was perceived as warmer and more competent, enhancing brand credibility, brand attitude, and purchase intentions. Content type did not moderate these effects. Study 2 replicated the effect of disclosure on warmth, and additionally found that content type moderated this effect (although the moderation did not operate as expected). No significant effects on competence emerged in this study. Theoretical and managerial contributions are discussed, especially regarding the strategic use of human authorship in content marketing.