People in some tropical countries used to use some plant extracts in folklore medicine as treatment of diabetes mellitus. Of these plants isCalligonum comsum (“orta”). The present work deals with the biochemical effects of the whole plant water extract given orally to the albino rats, normals and alloxan diabetics, as to fulfil its hypoglycemic effects on rats. The results showed that “orta” extract produced a hypoglycemic effect indicated by the decrease in blood sugar level. It was observed that the diabetic state in rats treated with 300 mg/kg body weight of “orta” extract, was alleviated, showing normal levels of blood glucose, liver fat and cholesterol contents. Liver proteins were still below the normal level in the rats. Gibenclamide, a hypoglycemic drug, was used for comparison with “orta” extract. Although it did alleviate the diabetic state, yet the liver fat and cholesterol contents were still higher than those of normal. Also the liver proteins were lower than the control levels.