Aim: This study aims to develop the Social Activities Scale for Community-Dwelling Older People Requiring Support (SASOS). Design: This study is a cross-sectional investigation. Methods: The participants were healthy older people (HOP; N = 140) and those requiring support (OPRS; N = 250). An anonymous questionnaire included items on SASOS, subjective health and ikigai (Japanese well-being concept). Criterion-related validity was examined using the Social Activity Index for Elderly People (SAI-E). Results: Seventy-five HOP and 157 OPRS provided effective responses. The scale (α = 0.805) had three subscales: "interactions with friends and neighbors (F1)," "close relationships with family (F2)" and "interactions with others through activity programs (F3)." SASOS and SAI-E scores were correlated (r = .558, p < .01), indicating criterion-related validity. In known-groups validity analysis, F1 were significantly higher among HOP and F3 were significantly higher among OPRS. Total scores correlated with perceived health (r = .240, p < .01) and ikigai (r = .419, p < .01).