Since home care service robots have become a crucial technological product in the intelligent healthcare and elderly care industry aimed at enhancing the quality of life for the elderly and addressing the insufficient supply of social elderly care resources, the work aims to explore the primary factors influencing their use by the elderly and provide a theoretical foundation and reference for age-friendly design research of home care service robots in intelligent healthcare and elderly care industry. A combination of qualitative and quantitative methods was employed. Through literature review, user interviews, open-ended questionnaires, factor analysis, and linear regression models, corresponding user evaluation scales and intention-to-use models were constructed to identify the main factors influencing the use of home care service robots by the elderly and explore the relationships and inherent connections between various factors. The principal factors identified included emotional companionship, interactivity, and functional quality. All three factors positively influenced the intention to use, with functional quality being the most significant factor, followed by emotional companionship and interactivity. Moreover, emotional companionship also positively influenced interactivity. In the design of home care service robots, priority should be given to the functional needs of the elderly in health management and household tasks, followed by emotional needs such as companionship, interactive communication, and age-friendly entertainment. Furthermore, consideration should be given to multimodal product interaction forms and the design of age-friendly interaction interfaces to improve the intention to use.