The purpose of this study was to investigate social participation in home-living patients with mild Alzheimer's disease (AD) and to identify predictors for low social participation. The study was based on baseline data from 330 home-living patients with mild AD who participated in The Danish Alzheimer Intervention Study (DAISY). Proxy-obtained information from primary caregiver assessed patients' social participation. The result showed that low social participation was present in mild AD. Significant independent predictors of low social participation were impairment in activities of daily living (ADL) and neuropsychiatric symptoms. The findings from this study add to the literature that social impairment is present even in the mild stage of AD. The findings underscore the importance of assessing social participation in mild AD as soon as few ADL skills are lost.