Background/Aim. Hyperglycaemia has a detrimental effect on the progress of micro/macrovascular complications in pa-tients with diabetes mellitus type 2 (T2DM). Additionally, all known complications in T2DM are coupled with oxidative stress developed from different metabolic pathways. The aim of this study was to estimate the quality of glucoregulation and the degree of oxidative stress in T2DM patients depend-ing on the applied therapeutic protocol and assess their corre-lation with clinical data and crucial biochemical parameters important for the development of diabetes complications. Methods. All included patients were divided into two groups: those treated with oral antidiabetic drugs (OAD) and those treated with oral antidiabetic drugs and insulin (OA-DINS). Thiobarbituric acid reactive substances (TBARS), to-tal sulfhydryl groups (TSH), the activity of superoxide dis-mutase (SOD), total nitrites (NOx), vascular endothelial growth factor (VEGF), and activities of matrix metallopro-teinase 9 (MMP9) were measured, together with lipid profile and routine biochemical parameters. All subjects were ana-lyzed for demographic characteristics and detailed medical his-tory as well as smoking habits and calculated for body mass index (BMI). Results. All patients were uniformly poor glu-coregulated and dyslipidemic. SOD activity was decreased, and lipid peroxidation was increased in the OAD group compared to OADINS. Deficient glucoregulation in both the OAD and the OADINS groups did not associate with an ox-idative state outcome. In both of these groups, the concentra-tions of VEGF and MMP9 were significantly higher than in controls. Conclusion. The better antioxidative outcome, ex-pressed with a normalized concentration of TBARS, pre-served TSH, and normalized SOD activity in T2DM patients treated with OADINS compared to those treated exclusively with OAD, suggests the need for more careful consideration of earlier insulin introduction into T2DM therapy in order to prevent the development of complications.