Family-based interventions involve family members in caring for patients with diabetes, but it is unclear whether they are effective in improving outcomes for type 2 diabetes (T2DM). This systematic review and meta-analysis aim to determine the effectiveness of family-based interventions in improving glycaemic control in T2DM patients. We identified 6163 abstracts. Eleven RCTs (n = 1421) met our inclusion criteria. The overall findings suggest that family-based interventions are effective in improving HbA1c, at 3-4 months follow-up and when the intervention is delivered by nurses, with modest effects. Consideration should be given to integrating family-based interventions in the primary care among cultures with greater family cohesion.