Background <p>Social isolation is a major problem for older adults. Increasing evidence suggests that perceived social isolation is linked to adverse physical and mental health outcomes among older adults. There is still a lack of qualitative interviews with Chinese community-dwelling older adults regarding social isolation. Guided by the Social Ecosystem Theory, this study aimed to explore community-dwelling older adults’ experiences of social isolation, the reasons why social isolation occurred, and the help they wished to receive.</p> Methods <p>This research was a descriptive qualitative study based on semi-structured face-to-face interviews, conducted in Zhengzhou, China. Used maximum variation and purposive sampling, 16 older adults were recruited from five communities. The qualitative study was guided by Husserl’s descriptive phenomenology and followed the Consolidated Criteria for Reporting Qualitative Research guidelines. Interviews were transcribed verbatim, and data were analyzed using Colaizzi’s seven-step method with the support of the qualitative data analysis software NVivo 12.0.</p> Results <p>A total of 16 interviews were completed. Five themes were identified: 1) Experiences of Social Isolation; 2)Micro systems: Personal factors that produce social isolation; 3)Mezzo systems: Social support network factors that produce social isolation; 4)Macro systems: Environmental factors that produce social isolation; 5)Desired assistance.</p> Conclusions <p>Community-dwelling older adults faced various challenges associated with social isolation. Social isolation in community-dwelling older adults stems from interconnected personal, familial, and environmental factors, often leading to negative emotional experiences. Multistakeholder collaboration—engaging individuals, families, communities, and policymakers—can help reduce social isolation and support emotional well-being.</p>