Contrasting data on reading ability in Alzheimer's disease patients have been reported in the literature. Recently Patterson, Graham and Hodges (1994) found that irregular words were misread by demented subjects, while regular words were read correctly. The present study hypothesizes that reading latency may be a sensitive measure of Alzheimer's patients reading impairment. Fifteen Alzheimer's patients were compared with 17 elderly normal subjects on three tasks that used the same set of concrete, regular words: a picture naming task, a word-picture matching task and a word-nonword reading task. The results of the study indicate that reading latency is longer in Alzheimer's patients than in normal subjects, and that misnamed and mismatched words are read with the same mechanism as nonwords.