Abstract Background: Diabetes Mellitus (DM) is a major interna-tional health problem characterized by an absolute or relative deficiency in the production or action of insulin, which results in hyperglycemia. Unfortunately, long term insulin adminis-tration in patients with DM results in insulin resistance. In this work, a novel therapeutic strategy of one of the ATP sensitive K channel opener KATP openers called Nicorandil was tried as an adjuvant agent in ameliorating CVD in exper-imentally-induced type I DM in rats. Aim of Study: The present study was designed to elucidate possible role of K channels in glucose homeostasis and regulation of the vascular reactivity in diabetic rats. Material and Methods: Fifty adult male albino rats were used in this investigation, divided into following groups control: Non-diabetic (C), diabetic (D), diabetic insulin treated (D + I), diabetic nicorandil treated (D + N) and diabetic insulin and nicorandil treated (D + I + N). Blood samples were collected for estimation of Fasting Blood Glucose (FBG) and (HbA1c), and vascular reactivity was examined using different vasoactive agents. Results: Type 1 DM resulted in substantial alterations in biochemical variables, as fasting blood glucose level, HbA1c, ABP and vascular reactivity. In our study there is significant decrease in fasting blood glucose level, (HbA1c) in both diabetic insulin (D + I) treated group and diabetic insulin and nicorandil (D + I + N) treated group in compared with the diabetic group, but with insignif-icant change between the two groups. There was significant improvement in vascular reactivity in diabetic insulin (D + I) treated group, diabetic nicorandil (D + N) treated group and diabetic insulin and nicorandil (D + I + N) treated group in compared with the diabetic (D) non treated group, but with insignificant change between insulin and nicorandil (D + I + N) treated group and non-diabetic (C) group. Conclusion: Nicorandil can be used as an adjuvant therapy in diabetic rats to improve vascular reactivity.