Background: Gestational Diabetes Mellitus (GDM) is a common pregnancy complication with significant maternal and fetal health implications. Early detection and management are critical to reduce the risks associated with GDM, but current diagnostic methods, such as glucose tolerance tests, are invasive and often fail to detect the condition at early stages.This paper explores the potential of serum zonulin as a novel biomarker for the early identification of GDM. Methods: This case-control study involved 100 healthy controls and 160 GDM patients .The study was approved by the institutional ethical committee. Serum Zonulin and HOMA IR, OGTT, HBA1C levels were measured, and their correlation was analyzed. Results: The present study's findings reveal significant differences in zonulin level between pregnant women with and without Gestational Diabetes Mellitus (GDM). Specifically, women with GDM had significantly higher levels of zonulin (33.26 ± 12.38 ng/ml) compared to women without GDM (13.29 ± 2.01 ng/ml).Conclusion: In conclusion, serum zonulin appears to be a promising biomarker for the early prediction of Gestational Diabetes Mellitus (GDM).