Background: Diabetes Mellitus is part of a metabolic syndrome comprises obesity, dyslipidemia, hypertension, and the changes in haematological parameters. Uncontrolled type 2 Diabetes Miletus (T2DM) is associated with multiple disorders including cellular, metabolic, and the blood disturbances leading to the vascular complications. Aim: To study of the hematological parameters and their correlation with blood pressure and renal function test among type-2 diabetes mellitus. Methodology: The present comparative cross-sectional study performed in Department of Physiology and Medicine of Integral Institute of Medical Sciences and Research, Lucknow. 70 uncontrolled DM (HbA1c >7.0%) either sex adult age group 30 to 70 years patients and 70 control DM (HbA1c <7.0%) of the same age and sex patients were enrolled in this study. eGFR was calculated by CKD-EPI creatinine equation (2021). Result: There were significantly elevated SBP, DBP, S. Creatinine, eGFR and RDW level in uncontrolled DM group (p<0.5). While Hb, RBC, TLC, MCV, MCH, MCHC and Platelet count level significantly decrease in uncontrol DM group (p<0.05). There was a strong correlation between diabetes profiles, blood pressure and kidney function in DM patients. In uncontrolled diabetes group MCV, MCH, MCH and Platelet counts were negatively significant correlation with SBP, DBP, S.creatinine and eGFR. Conclusion: RBC indices (MCV, MCH, MCH and Platelet counts) in uncontrol DM group was negatively significant correlation with FBS, PPBS, SBP, DBP and S, creatinine; but positive significant correlation with eGFR.