According to neuropsychological models of anosognosia, there is a failure to transfer on-line awareness of dysfunction into a more generalised long term belief about memory function in Alzheimer's disease. This failure results in specific metamemory deficits for global predictions: patients overestimate their performance before the task but are able to monitor their memory performance after having experienced the task. However, after a delay, they are still not able to make accurate predictions. As previous work has mainly focused on long-term memory, the present study investigates this issue in short-term and working memory. Using both global and item-by-item metacognitive judgements in a digit span task, we showed that Alzheimer's disease patients are as accurate as older adults in monitoring their performance despite impaired memory. When they have the opportunity to test themselves, or when they have already performed the task, patients are able to use feedback to adjust their metacognitive judgements. Overall, these results show that even for a relatively complex task, patients with Alzheimer's disease are aware of their difficulties in the here-and-now.