Attribute-framing bias (AFB) refers to addressees' bias in evaluating positively framed objects (80% success) more favorably than negatively framed ones (20% failure), although they are logically equivalent. The novelty of the current study is in examining conditions in which AFB occurs or does not occur. Typically, AFB is examined for favorable outcomes (e.g., 80% success / 20% failure); the current study extended the examination to unfavorable outcomes (e.g., 80% failure / 20% success). According to fuzzy-trace theory, information is encoded both as a detailed verbatim representation and as a fuzzy gist representation, and AFB is elicited by the vague gist representations that maintain either the positive or the negative valence of the message. The current study offers a novel insight into the relationship between gist and verbatim representations in AFB by examining how it is moderated by the favorability of the outcomes. In three experiments, we focused on the perceived reliability of news items. As fake news has become an issue of major concern, some news media publish truthfulness evaluations; however, the framing of such evaluations may bias the perceived reliability of news. Hence, we examined to what extent the favorability of the outcomes moderated AFB in perceived news reliability. The results showed that attribute framing biased the perceived reliability of news when truthfulness outcomes were favorable (80% true / 20% fake) but not when outcomes were unfavorable (20% true / 80% fake). We discuss the theoretical implications of these findings to the understanding of AFB and their practical implications concerning the perceived reliability of news.