The relationship between physical disability and depressive symptoms has been associated with social support. Different aspects of social support may play distinct roles in health-related quality of life. The aim of this study was to examine the mediation of social support in the relationship between physical disability and depressive symptoms among old people in Mainland China. Subjective support and utilization of support mediated the relationship between ADL and depressive symptoms, with the indirect effect of subjective support and utilization of support at 0.038 and 0.030 respectively (the total effect was 0.180). Subjective support was negatively associated with depressive symptoms in independent elderly people, utilization of support was negatively associated with depressive symptoms in partially dependent elderly people, and utilization of support had a greater association with geriatric depressive symptoms than subjective support in severely dependent elderly people. Social support mechanism and positive psychological intervention should be established and introduced in accordance with the physical disability of the elderly people, to protect them from depressive symptoms.