BACKGROUND: Mobile health (mHealth) for breast cancer care can greatly benefit patients' symptom management. Although research supports the effectiveness of mHealth, older adult patients with breast cancer often face difficulties using it, hindering them from accessing effective symptom management possibilities. Understanding the preference for mHealth among this population is crucial for providing insights into effective mHealth design. OBJECTIVE: This study aimed to better understand the symptom management preference using mHealth for Chinese older adult patients with breast cancer and use the approach of personas to inform the mHealth design. METHODS: This was a descriptive qualitative study. In total, 17 patients with breast cancer aged 60 years and older were recruited from tertiary hospitals in Shanghai, China, using purposive sampling. Data were collected through one-on-one interviews. Content analysis was used to identify the factors that influence participants' symptom management preference using mHealth. The categories of influencing factors of preference informed the persona template and guided the development of the persona. RESULTS: We identified 3 major categories affecting participants' preference for mHealth, including social interaction patterns, mHealth literacy, and symptoms. The following five personas were developed: (1) Positive Manager, (2) Dependent Parent, (3) Management Isolationist, (4) Image Manager, and (5) Clinician Dependent. We provide insights into how these personas can be used when designing and implementing mHealth for symptom management support. CONCLUSIONS: Key factors influencing symptom management preference using mHealth among Chinese older adult patients with breast cancer and personas developed based on that can foster a better understanding of this population and initiate future mHealth design and implementation.