In this study serum zinc , copper, magnesium,reduced glutathione, and alanine aminotransferase enzyme levels were estimated in 102 patients and compared with 50 healthy controls. The patients were divided into four groups: Patients with insulin dependent diabetes mellitus (IDDM). Patients with non- insulin dependent diabetes mellitus (NIDDM). Patients with both diabetes and hypertension. Patients with hypertension. Serum zinc, serum copper, and serum magnesium were determined by using atomic absorption spectrophotometer, while serum reduced glutathione and serum alanine aminotransferase enzyme were determined by spectrophotometric analysis. The results in this study showed : 1. Significant decrease (P < 0.05) in serum zinc levels in all patients compared with healthy controls. 2. . Significant increase (P < 0.05)-in serum copper levels in all patients compared with healthy controls. 3. Significant decrease (P < 0.05) in serum magnesium levels in all patients compared with healthy controls. 4. Significant decrease (P< 0.001) in serum reduced glutathione levels in all patients compared with healthy controls. 5. Significant increase (P< 0.05) in serum alanine aminotransferase enzyme levels in NIDDM patients, while the other patients showed no differences as compared with healthy controls.