The traditional view of oral reading ability in patients with dementia holds that it is a preserved skill even if there is a general impairment to lexico-semantic processing ability. Recently, this view has been challenged by studies showing that the oral reading ability of patients with dementia can deteriorate over the course of the disease. These studies have found that the oral reading of irregular English words is more prone to error than the oral reading of regular words by patients with dementia suggesting that the oral reading of irregular words depends upon support from semantic memory. Relatively little is known about the oral reading abilities of Chinese-speaking dementia patients. This paper reports on the results of a study of the language processing and the oral reading ability of Chinese speakers with probable dementia of the Alzheimer's type (DAT). DAT patients displayed impairment on tests of oral reading as well as impairment on tests of semantic memory, confrontation naming and word comprehension. The results also show significant effects of regularity, frequency and imageability on the oral reading of DAT patients. It is argued that Chinese-speaking DAT patients display a pattern of language impairment similar to their English-speaking counterparts and, moreover, that normal oral reading of Chinese characters may depend critically upon the integrity of semantic memory.