Many people distrust their memories, because they believe themselves prone to omission errors such as forgetfulness, and/or commission errors such as misremembering. However, the most popular psychometric measure of memory distrust—the Squire Subjective Memory Questionnaire (SSMQ)—only probes people’s beliefs about omission errors, not commission errors. The present research describes a new memory distrust measure that assesses the latter kind of metamemorial belief. Two studies (combined N = 797) showed that our 20-item Memory Distrust Scale (MDS) has good psychometric properties, and is correlated with—but distinct from—the SSMQ. Participants in Study 2 described eight childhood events, and rated their recollection of and belief in the oc...