Background: Diabetes Mellitus is a chronic disease that needs complex management. Social support, especially family support is an important factor in diabetes management but usually unnoticed. Aim: To determine the effectiveness of diabetes education for family member on family perception about diabetic, family support, self-care patient and metabolic control (HbA1C). Methods : This research was a Randomized Control Trial study in diabetes outpatient at RSUD Ulin Banjarmasin used a purposive sampling based on HbA1C data at hospital laboratory (HbA1C > 7%). Family member in intervention group received an education in four sessions and in control group not get the intervention anything. Perception, family support, and self-care was assessed by Brief Illness Perception Questionnaire (BIP-Q), behavior support questionnaire (Part of Multidimensional Diabetes Questioner), and The Summary of Diabetes Self-Care Activities (SDSCA). Glycemic control was assessed by HbA1c. All of the parameter were collected pre and post intervention in control and intervention group. The effect of intervention was analyzed with two sample comparative analysis. Result: Twenty-two patients (plus their partners) were enrolled and randomized as follows: 10 to the intervention and 12 to the control group. The analysis showed family perception about diabetic in personal control and illness comprehensibility variable has a significantly different (p=0.021 and p=0.001) and the family support increase significantly after intervention (p=0.023). The improvement average of self-care and decrease of HbA1c in intervention group more good than control group (4.72.91 vs 1.244.98) and (1.421.35 vs 0.751.90), but not significant different. Conclusion: Education intervention to the family member did not give a significant influence on the improvement of HbA1c, self-care, and perception variable such as consequences, timeline, treatment control, identity, representation and concern and emotional. But can provide a good influence on improved behavioral family support and perception variable such as personal control variables and illness comprehensability. Keywords: Diabetes Mellitus, Family education, Glycemic control, Behavior support, perception, self-care.