© 2015 Production and hosting by Elsevier B.V. on behalf of Egyptian Society of Anesthesiologists. Background Hyperglycemia is common among critically ill patients and is associated with increased morbidity and mortality and there is no clear answer to the question: which to apply tight or conventional glycemic control? Objective Evaluation and comparison of the effects of tight versus conventional glycemic control on critically ill patients in our surgical intensive care unit (ICU). Design Prospective randomized controlled trial. Methods 120 Patients were divided into two groups: group (I) received intensive insulin therapy targeting blood glucose level between 80 and 110 mg/dl, who referred to as intensive treatment group, and group (II) received conventional insulin therapy targeting blood glucose level between 150 and 200 mg/dl, and referred to as conventional treatment group. Results 120 Patients were enrolled in the study, the incidence of hypoglycemia (blood glucose <70 mg/dl) was 29.09% in group I who received intensive insulin therapy versus 6.15% in group II who received conventional insulin therapy (p value 0.000) with no demonstrable complications, regarding mortality rate, impairment of Liver function tests, change in total leukocytic count, the need for red blood cell transfusion, ICU stay and Total hospital stay and we reported no statistical significant difference between the two groups. Conclusion Tight glycemic control for critically ill patients in ICU in poor resources countries showed increased incidence of hypoglycemia with no significant benefits when compared with conventional glycemic control.