Serum magnesium, zinc and total cholesterol were evaluated in 40 Nigerian patients suffering from type-2 diabetes mellitus (21M, 19F) and 20 (14M, 6F) apparently normal non diabetic control subjects. The mean age of the diabetic patients was similar to that of controls (p > 0.05). The mean duration of the disease was (4.7 + 0.7 SEM) in these patients. Fasting blood glucose and total cholesterol were significantly higher in diabetics than in non diabetic control subjects (p > 0.001). The serum total cholesterol showed inter-group variation when the patients were classified into four different age groups. In contrast, the serum level of magnesium (Mg) and zinc (Zn) were significantly lower in diabetics than in controls (p > 0.001). There were no significant correlation between glucose and the minerals, Mg. and Zn. Serum total cholesterol showed a significant positive correlation with magnesium (r = 0.6: p > 0.001), while the correlation with zinc was not significant. In type-2 diabetic mellitus the concentration of both Mg and Zn levels were significantly reduced, probably suggesting lower antioxidant status in this condition. The implication is the greater susceptibility to LDL-cholesterol oxidation. The attendant risk of development of premature Coronary Heart Disease is discussed. Magnesium and zinc are nutritional minerals that play crucial roles in the regulation of carbohydrate and lipid metabolism.