Introduction: Offspring of gestational diabetes mellitus (GDM) mothers are at high risk of developing insulin resistance, type 2 diabetes mellitus (T2 DM), and cardiovascular complications later in life. So, screening maternal blood glucose during pregnancy and identifying high-risk infants immediately after birth is necessary to prevent the potential long-term implications. Aim: To correlate the maternal fasting and post-prandial blood glucose withfetal insulin level. Materials and methods:A case-control study, was conducted at Chettinad Hospital and Research Institute, India, between May 2019 to May 2020. A 75-gram OGTT was performed among pregnant women between 24 to 28 weeks of pregnancy for diagnosing GDM according to American Diabetes Association (ADA) guidelines. 94 GDM mothers and Non-GDM mothers and theirnew-bornswere taken up for this study. 2.5ml of maternal venous blood was collected in a vacutainer containing sodium fluoride and EDTA as an anticoagulant for FBS and PPBS estimation. Some mothers on induction of labor were posted for emergency LSCS (for failed induction and non - progression of labor) and some had normal vaginal deliveries. Plasma FBS and PPBS estimation in the mother’s blood sample was assayed by the Hexokinase method in Siemen'sDimension RxLMachine immediately after centrifugation. 2.5ml of umbilical cord blood was collected in a vacutainer without an anticoagulant after the 2nd stage of labor. 0.5 ml of cord blood serum was separated and stored at -80°C in an eppendorf for later estimation of insulin by CLIA method in Beckman Coulter – Access 2 Immunoassay System. Independent students’ t-tests and Pearson’s correlation were used as statistical methods. p-value <0.05 is considered significant. Results: There is a positive correlation and significant difference between maternal FBS, PPBS, and fetal insulin levels in the GDM group (p-value 0.008, r-value 0.272 and p-value 0.005, r-value 0.286) compared to the Non-GDM group (p-value -0.087, r-value 0.243 and p-value 0.018, r-value 0.212). Conclusion: Significant hyperinsulinemia was noted in the offspring of the GDM group compared to the NON-GDM group.Those hyper-insulinemic babies are at very high risk of developing obesity, metabolic syndrome, and type 2 DM in the future and possess a threat to society.