This study aims to test the following two hypotheses. First, the life satisfaction of the elderly is not directly affected by their resident status. Second, guided by activity theory and symbolic interaction theory, social activities outside the home (paid work, unpaid work, and hobby/leaning activity) have a greater effect on life satisfaction for elderly people living alone than those living with family members. Participants were 1,774 elderly people who had participated in courses for the elderly to learn various topics, with a final study sample size of 1,539 after flawed survey sheets were removed. T-test findings showed that resident status did not directly influence life satisfaction. A multi-group structural equation model analysis verified that unpaid work has a greater effect on the life satisfaction of the elderly living alone than the one of elderly living alone. These results suggest that unpaid work acts as a buffer effect to decreased life satisfaction.