ABSTRACT: BACKGROUND:The purpose of this study was to examine the differences of timewise changes in life-space mobility between elderly people living alone and those living with others among community-dwelling elderly people from a day care facility with a rehabilitation service for seniors. METHODS:The present study used a longitudinal design with repeated measures every 3?months. In conformity with our inclusion criteria, this study included 233 community-dwelling elderly users of a day care facility with rehabilitation services for seniors in Japan. We analyzed the life-space assessment (LSA) scores collected at five time points (baseline, 3?months, 6?months, 9?months, and 12?months) using mixed-effects models with random intercepts and slopes over time. In the present study, the explanatory variables of interest were time, and living situation (living alone or with others). As possible confounders, we considered the following: (a) age, (b) sex, (c) social frailty, (d) physical frailty, (e) mild cognitive impairment (MCI), (f) depression, and (g) economic satisfaction. RESULTS:The mean age of participants was 78.9?years (SD?=?7.7), their mean LSA score was 60.1 points (SD?=?25.7), and 42.9% of the participants were men. After adjusting for age, gender, frailty, depression, MCI, and economic satisfaction, the mean LSA score of older adults who lived with others was significantly lower (7.42 points, 95%CI?=?-?18.30 to -?0.15, p?=?0.048) than that older adults who lived alone. DISCUSSION:Community-dwelling older adults who used a day care center with rehabilitation services and lived with others had a smaller life-space at baseline than those who lived alone. This suggests that there is a need to pay more attention to social frailty among both older adults who live alone and those who live with others. CONCLUSIONS:According to a multilevel analysis growth model, elderly persons who lived with others had significantly lower life-space mobility than those who lived alone.