Metacognitive beliefs about the benefits of rumination are associated with rumination and depression; however, the direction of these relationships remains unclear. Two experiments examined whether individuals with high positive beliefs about rumination engaged in more rumination following a laboratory-based stressor than individuals with low levels of such beliefs. In Study 1, participants with high levels of positive beliefs reported more rumination following receipt of negative feedback on a forced-failure anagram task. In Study 2, participants with high levels of positive beliefs reported more rumination compared to participants with low levels of positive beliefs, regardless of whether they received negative feedback, positive feedback or no feedback on their performance. Our findings demonstrate the importance of positive beliefs about rumination, and highlight the utility of treatment approaches that aim to reduce rumination by targeting such unhelpful metacognitive beliefs.