Background <p>Conspiracy beliefs pose a societal challenge, yet the processes through which they emerge remain debated. One pathway to conspiracy beliefs that has received limited attention is the role of emotional responses to relative deprivation (RD). RD — the perception of being unfairly disadvantaged— elicits negative emotions such as anger and disgust, which may in turn foster conspiratorial interpretations.</p> Methods <p>Across eight preregistered studies (<i>N</i> = 3,306), we experimentally induced direct, individual-level RD using a validated unfair-outcome paradigm and assessed anger, disgust, and (exploratorily) anxiety. All studies measured conspiracy mentality and specific conspiracy beliefs.</p> Results <p>We synthesized study-wise effects in a random-effects mini–meta-analysis. Experimentally induced RD reliably increased negative emotional responses (i.e., anger and disgust across all studies). Anger and disgust, but not anxiety were associated with both conspiracy mentality and specific conspiracy beliefs. Mini–meta-analytic mediation analyses showed consistent indirect effects of RD on both conspiracy outcomes through negative emotions. Total effects of RD on conspiracy beliefs, however, were very small and varied in direction across studies, underscoring the importance of emotional mechanisms.</p> Conclusions <p>The findings indicate that direct experiences of RD may promote conspiracy beliefs indirectly through heightened anger and disgust. This work highlights results that are consistent with an important role of momentary emotional responses in the emergence of conspiracy beliefs and advances understanding of the affective mechanisms linking RD to conspiratorial thinking.</p>