The Integrated Circuit tag monitoring system became available to measure wandering in terms of the distance moved by dementia patients. The purposes of the study were to describe degree of ambulation in patients with Alzheimer's disease (AD) and to examine factors associated with the distance moved. AD patients were recruited at a dementia care unit in Asakayama Hospital, Osaka, Japan. The monitoring system generated the distance moved per day. Demographic and clinical data were abstracted from medical records. Mini-Mental State Examination was used to measure cognitive function. A multiple linear regression was used to predict the distance moved per day. The research was approved by the ethics committee of the university and the hospital, and written informed consent was obtained from the patients' proxies. Majority of the AD subjects monitored had moderate to advance stage of dementia. Patients' age and cognitive function were predictors of the median distance moved/day, and these two variables explained almost half of the variance. Older age and lower cognitive function were associated with reduced median distance moved per day in AD patients.