This study investigated how sixth graders’ credibility evaluation self-efficacy was associated with their ability to evaluate the credibility of online texts. Students (N = 265, Mage = 12.45) worked in a web-based environment, where they read and evaluated two more credible texts and two less credible texts that required confirming and questioning the texts’ credibility, respectively. Students were asked to evaluate the author’s expertise, the author’s benevolence, and the quality of evidence in each text. They were also asked to assess their credibility evaluation self-efficacy during the task. The structural equation model indicated that students’ self-efficacy was positively associated with their ability to confirm the more credible texts but not with their ability to question the less credible texts. The instructional implications of this study are discussed.