Aim of the study was investigation of influence of diabetes mellitus (DM) on rate of detection of multifocal atherosclerosis (MFA) in patients with ischemic heart disease (IHD) at examination before coronary artery bypass grafting (CABG). We retrospectively analyzed 2411 hospital forms of patients with IHD subjected to CABG. DM was found in 317 patients (group 1). Control group (n=350) comprised patients of comparable sex and age without DM. Clinico-anamnestic data, parameters of coronary angiography, ultrasound and angiographic study of the aorta, brachiocephalic and peripheral arterial beds were compared between these groups. Patients with diabetes compared with patients of the control group more frequently had increased thickness of intima media complex (92 and 77%, respectively; p=0.0001). Simultaneous involvement of 2 or more arterial beds were detected in 46.1% of patients with DM and in 33.1% of control patients. Involvement of only one (coronary) arterial basin was more frequent in patients without DM (p=0.0001). Multifactorial analysis showed that independent effect on detection of MFA produced intima media thickness, presence of DM and history of acute disturbance of brain circulation. Thus among patients with IHD MFA before CABG was found in 46.1% of patients with DM and 33.1% of similar sex and age patients without DM. Patients with DM require focused examination for detection of manifestations of MFA and conduct of necessary curative and preventive interventions.