Abstract: On the light of the antihyperglycemic effect of bark extract of S. campanulata (SC) that was detected by few previous studies, we aimed to investigate the glucose lowering effect of flowering branch and bark extracts of SC and its possible mechanistic background. The crude methanolic extracts of the bark and the flowering branch were tested for their anti-hyperglycemic effect in forty mice divided into 5 groups: group 1 received only 1% carboxymethyl cellulose (CMC) as negative control, all the other groups were subjected to alloxan induction of diabetes mellitus from which second group left without any treatment as positive control, the third and fourth groups were administrated the methanolic extracts of the flowering branch and bark respectively in dose of 500 mg kg–1. b.wt. and the fifth group received metformin in dose of 150 mg kg–1 b.wt. At the end of treatment period blood levels of glucose, insulin, triacylglycerols and cholesterol were estimated; in addition to the evaluation of muscle tissue concentration of insulin receptors. A significant reduction of blood glucose was noticed after 2 h of treatment with bark extract but not with flowering branch extract (p<0.05), moreover a significant rise in concentration of insulin receptors was found in bark extract and metformin treated groups as compared to control group (p<0.05). Consequently, we concluded that bark extract of S. campanulata may have a prospective anti-hyperglycemic therapeutic effect in diabetes; this influence could be through modifying the tissue expression of insulin receptors.