Humorous advertisements attract attention and entertain consumers. Nonetheless, attempting humor is risky because consumers may be offended by failed humor attempts. We propose another reason that attempting humor is risky: humorous advertisements can hurt brand attitudes by eliciting negative feelings — even when consumers find the ad funny. Three experiments and one correlational study demonstrate that humorous marketing is more likely to hurt the advertised brand when it (1) features a highly threatening humorous ad rather than mildly threatening ad, (2) makes fun of a subset of the population rather than people in general, and (3) motivates avoidance rather than approach. We conclude by offering five guiding questions for marketers who want to use humor to attract attention and entertain consumers without inadvertently hurting brand attitudes.