Mindfulness-based interventions have been suggested as ways of improving mood and cognition in people with dementia. Existing findings suggest possible benefit from a mindfulness-based group intervention. However, it is unclear whether any structured group activity (rather than mindfulness practice per se) would produce the same benefits, particularly since dementia may impact mindful attention ability. Consequently, we investigated the potential impact of having dementia on mindful attention. We compared the performance of 34 people with dementia recruited from memory services with 55 community-recruited older people on measures of mindful attention, cognitive flexibility, and cognition, as well as putative nuisance variates of depression, anxiety and premorbid intellectual ability. The groups differed significantly on a range of demographic characteristics and some neuropsychological and mood measures. However, neither the primary prediction (that there would be a large effect size difference between groups, with people with dementia performing significantly more poorly on a measure of mindful attention to the breath), nor the secondary prediction (that performance on this measure would positively correlate with measures of executive function and overall cognition) was supported. We concluded that a diagnosis of dementia may not have a large effect on mindful attention, with consequent implications for future research