Family members play a vital role in both helping and undermining diabetes mellitus selfmanagement practices. This qualitative study aimed to explore the potentially unmet needs of family function to support diabetes self-management (DSM) practices. In-depth interviews and focus group discussions (FGDs) were conducted among different key informants, including uncontrolled T2DM patients, caretakers and healthcare providers (HCPs) at community health centres. An open-ended approach was applied to elicit responses from the key informants. A total of 22 participants were involved in this study. All interview and FGD processes were audiorecorded and transcribed verbatim. The results found that all key informants addressed six core themes, with sub-themes to describe the unmet needs of family function to support DSM practice. The critical unmet needs of family function include: 1) Lack of problem-solving skills to deal with poor diabetes management; 2) Ineffective communication and refusal to share the burden of diabetes management; 3) Lack of affective responsiveness to encourage patients' compliance; 4) Lack of affective involvement in DSM; 5) Insufficient family roles in supporting patients; 6) Poor behaviour control of T2DM. Our findings provide insights into how family function may influence the adoption and maintenance of healthy behaviours among diabetic patients. Since health providers seek new approaches to improve DSM practices, this valuable finding was essential to understand how family function can improve and empower patients in DSM practice.