Diabetic mellitus is a group of metabolic disorders in which there are high blood sugar levels over a  prolonged  period,  diabetes  can  causes  many  complications.  The trace  element vanadium has unclear biological functions. Vanadate, an oxidized form of vanadium, appears to have an insulin-like action, the effect of vanadate on blood glucose was assessed in male Wistar rats after they were made diabetic with Streptozotocin (STZ). The animals were fasted overnight and a single intraperitoneal injection of a freshly prepared solution of STZ (55 mg/Kg b.wt) in 0.1 M cold citrate buffer (PH 4.5) was given to induce diabetes. The animals were  allowed  to  access  to  5  per  cent  glucose  solution  overnight,  to  prevent  total hypoglycemia, induced by STZ by massive pancreatic insulin release. The animals were considered as diabetic, if their blood glucose values were above 250 mg/dL on the third day (72 hours) after STZ injection. The treatment was started on the fourth day after STZ injection and the day was considered as first day of treatment. The treatment was continued for 15 days. Diabetes causes disturbance in liver and kidney functions and causes hyperlipidemia also decreased   the antioxidant activity; after the treatment with the two novel vanadium complexes , all functions of liver (Alanine transferase, Aspartate transferase and total protein) and kidney functions ( Creatinine and urea ) were improved. Also, lipid profile (total cholesterol and Triglycerides) level decreased and the activity of antioxidant enzymes (Superoxidedismutase, Glutathione peroxidase, Glutathione reductase and Malonodialdhyde) improved.