The objective of this study was to find variables that showed significant associations with cognitive decline and memory loss in visual, auditory, olfactory, and balance functions. Seventy-six elderly people aged 65 or older participated in the experiment, received the aforementioned functions’ assessments, and underwent cognitive screening. Participants were divided into the normal cognitive (NC) and lower cognitive (LC) groups on the basis of cognitive function test scores, and the LC group was divided into the lower-MIS and normal-MIS groups on the basis of memory index scores (MISs). The LC group had less balance, hearing, and olfactory functions than the NC group, and the lower-MIS group had less visual and auditory functions than the normal-MIS group. The performance of the classification model made of variables was evaluated as the area under the receiver operating characteristic curve. The performance was shown to be good. Therefore, this study can be the basis for the development of tools for the early diagnosis of dementia and the creation of a smart environment.