Background: Previous research has shown that sophisticated epistemological beliefs exert a positive influence on students' learning strategies and learning outcomes. This gives a clear educational relevance to studies on the development of methods for promoting a change in epistemological beliefs and making them more sophisticated. Aims: To investigate the potential for influencing domain-specific epistemological beliefs through a short instructional intervention. Sample: On the basis of their performance on a preliminary survey of epistemological beliefs, 58 students at a German university (87.7% females) with a mean age of 21.86 years (SD=2.88) were selected. Half of them had more naive beliefs and the other half had more sophisticated ones. Methods: Participants were randomly assigned to one of two groups: one whose epistemological beliefs were challenged through refutational epistemological instruction or another receiving non-challenging informational instruction. The treatment effect was assessed by comparing pre- and post-instructional scores on two instruments tapping different layers of epistemological beliefs (DEBQ and CAEB). Data were subjected to factor analyses and analyses of variance. Results: According to the CAEB, the naive group receiving the refutational epistemological instruction changed towards a more sophisticated view, whereas the sophisticated students receiving the informational instruction changed towards an unintended, more naive standpoint. According to the DEBQ, all research groups except the naive refutational group revealed changes towards a more naive view. Conclusions: This study indicates the possibility of changing domain-specific epistemological beliefs through a short-term intervention. However, it questions the stability and elaborateness of domain-specific epistemological beliefs, particularly when domain knowledge is shallow.