Low-education women, a substantially older population, are subject to increased risks of metabolic syndrome and consequent cardiometabolic diseases; early detection and effective management were urgently needed. Ninety-nine women with metabolic syndrome, age 61 and education ≤ 6 years, from four community units were randomly assigned to either a self-management intervention (n = 51) or a control arm (n = 48). The intervention consisted of five dimensions, physical activity and diet modifications (daily exercise classes and two nutrition courses), goal setting, coaching and peer support, problem-solving, and self-monitoring. The control arm received an education leaflet. Assessments were performed at baseline, six months, and 18 months. Compared with the control, the intervention participants improved the overall rate of meeting the recommended servings for six health foods, including vegetables, dairy products, and nuts (except whole grains, fruits, and protein); the rate of meeting regular leisure-time physical activity; and criteria biomarkers—waist circumference, fasting blood glucose, high-density lipoprotein cholesterol (except blood pressure and triglycerides); as well as body weight and body mass index; consequently decreased the number of risk factors and rate of metabolic syndrome. In conclusion, the multidimensional self-management intervention improved physical activity, healthy eating, and metabolic syndrome risks among low-education women with metabolic syndrome.