Abstract Background Type 1 diabetes mellitus (T1DM) is an inflammatory disease of the pancreatic islets that results in absolute insulin deficiency and the consecutive hyperglycemia due to immune-mediated beta cell destruction throughout the globe, the incidence of T1DM is increasing at 3% to 5% per year Purpose To study the relationship between DPP-4 serum level, TNF a concentration measurements, and insulin sensitivity in T1DM patient Patients and Methods Patients were selected from the inpatient department of National Institute of Diabetes and Endocrinology during Januaray 2017, venous blood samples were collected to measure Serum level of creatinine, C-peptide, HbA1c%, DPP-4, TNFα . Measurement of eGDR was done using the formula 24.31 - 12.2 x (WHR) – 3.29 x (BLP) – 0.57 X HbA1c Study Design Cross sectional study that included 80 patients with type 1 Diabetes, Results The study population was divided according to median eGDR value of 6.125 mg kg-1 min-1 The group with higher IR(eGDR≤ 6.125)had higher value of DPP-4 enzyme level (1127.3 ± 40.9 ng/ml vs. 870.6 ± 30.2 ng/ml, p < 0.001) and TNF α concentration (11.4 ± 4.8 pg/ml vs 5.3 ± 1.6 pg/ml, p < 0.001). TNF α concentration negatively correlated with eGDR (r= -0.515, p value <0.001) DPP-4 level negatively correlated with eGDR (r= -0.826 and p value <0.001) while DPP-4 was positively correlated with TNF α (r = 0.441 p value ≤ 0.001)