Individuals with amnestic mild cognitive impairment (aMCI) often complain of difficulty remembering to carry out intended actions, consistent with findings of impaired prospective memory (PM) in this population. In this study, individuals with aMCI (N = 27) performed worse than healthy controls (N = 27) on the Memory for Intentions Screening Test (Raskin, 2004), including on time- and event-based subscales, and recognition of the intentions. The aMCI participants made more errors overall, but the proportion of the various error types did not differ between the two groups. Across all error types, both groups made more retrospective than prospective errors, especially on event-based PM tasks. Overall, the findings suggest that PM impairment in aMCI is associated with deficient cue detection involving both automatic (as in event-based tasks) and more strategic detection (as in time-based tasks) processes. These difficulties are likely due to a combination of problematic retrospective episodic memory (e.g., reduced encoding and/or consolidation of cue-intention pairings) and executive functions (e.g., decreased self-initiation, attention switching, and/or inhibition on memory tasks). Formal assessment of PM may help characterize the nature of the memory impairment among individuals with aMCI in clinical neuropsychological evaluations.