Executive functions are the key asset for achievement of autonomy and independence in activities of daily living and their impairment is a major determinant of poor functional outcomes in people with dementia. Performance based evaluation of executive function in using daily living activities is an important area of study for people with dementia. This study is to validate a performance-based evaluation, the Chinese Multiple Errands Test (Chinese-MET) for a group of sixty people with dementia. Their functional disabilities profile was examined. The Chinese-MET was administered concurrently with validated instruments, such as the Lawton Instrumental of Daily Living- Chinese Version (Lawton IADL-CV), the Montreal Cognitive Assessment Hong Kong Version (MoCA-HK) and the Chinese Version of the Disability Assessment for Dementia (CDAD) for reliability and validity testing. The index of performance in the Chinese- MET showed significant correlation with the function score of Lawton IADL-CV (r = 0.86, p< 0.001), the cognitive function score of HK-MoCA (r = 0.86, p < 0.001), and the CDAD (r = 0.44, p < 0.001). Analysis of the relationship with sociodemographic factors indicated that the Chinese-MET was not correlated with gender and education, and that the correlation with age was low. The Chinese-MET was shown to be a reliable and valid instrument in assessing executive function of subjects with dementia in Chinese population. The Chinese-MET helps to identify executive function deficits which previously missed by only standard paper and pencil and office based measures. This study made a contribution beyond by introducing the Chinese-MET, so far no validated MET has not been done specifically for people with dementia.