The state of the cardiovascular system was studied in patients with type 2 diabetes mellitus and thyroid disorders in the absence of thyroid gland dysfunction. 76.9% of the 302 patients with DM2 had thyroid pathology; in 23,8% it was not previously diagnosed. We compared euthyroid patients with DM2 without thyropathies and with diffuse-nodular changes largely in the form of diffuse-multinodular non-toxic goiter and autoimmune thyroiditis (AIT). It was demonstrated that enhanced frequency of thyroid disorders is related to DM2 duration and vascular complications. The predominant thyroid pathology in DM2 was diffuse-multinodular non-toxic goiter followed by autoimmune thyroiditis. Nodular forms in AIT without DM2 are rare whereas multinodular forms in the patients with DM2 and AIT occur much more frequently. Node formation is related to such DM2 complications as diabetic nephropathy, angiopathy, and retinopathy. The study showed that the frequency of both non-specific clinical changes characteristic of thyroid dysfunction and of specific cardiological manifestations in euthyroid patients with DM2 and thyroid pathology significantly increases especially in the presence of AIT and anti-thyreoperoxidase antibodies, regardless the form of thyropathy. It may be due to immuno-inflammatory cross talk between thyroid and myocardial tissues. Patients with DM2 and diffuse-nodular changes in the thyroid gland more frequently presented with different forms of atrial fibrillation and high-grade ventricular extrasystole than patients with AIT or DM2 without thyropathies. It is concluded that euthyroid patients with DM2 need their thyroid function to be regularly monitored. The development of examination algorithm is an object of further studies.