Background: Knowledge from educational research frequently contradicts preservice teachers' prior beliefs about educational topics. Such contradictions can seriously affect their attitudes towards educational research and can counteract efforts taken to establish teaching as a research-based profession. Aims: Inspired by Munro's (2010, "J. Appl. Soc. Psychol.," 40, 579) work on science discounting, this study examined whether preservice teachers tend to devalue the potency of educational research when evidence contradicts their beliefs. Sample: We used data from 145 preservice teachers from different German universities. Methods: In an experimental design, participants indicated their prior beliefs about an educational topic (i.e., effectiveness of grade retention) before and after reading either confirming or disconfirming scientific evidence. Dependent variables were, first, whether participants devalued the potency of science to study this focal topic and whether they generalized this devaluation to further related and unrelated topics; second, whether participants preferred non-scientific over scientific sources to inform themselves about the focal topic as an indirect measure of science devaluation. Results: Interaction effects on both outcome variables confirmed that participants devalued educational research and its sources when scientific evidence conflicted with their prior belief. Yet, results did not corroborate any generalization of devaluation to further topics. Despite the devaluation, participants indicated belief revision in the direction of the evidence read. Conclusions: Preservice teachers may indeed critically question educational research when scientific evidence conflicts with their prior beliefs. However, they may also adapt their assumptions in light of strong evidence. More research is needed to clarify the conditions of devaluation and belief revision.