Background: Gestational diabetes mellitus (GDM) is a common condition with risks for mother and baby. Type 2 diabetes mellitus (T2DM) and obesity are occurring with increasing frequency, and the incidence of GDM reflects this trend. Objective: The aim of the study was to determine the relationship between first trimester elevated uric acid levels and subsequent development of gestational diabetes mellitus during pregnancy. Patients and Methods: The study included 78 pregnant women in the first trimester attending the outpatient clinic of Zagazig University Hospitals, Zagazig for antenatal care. In this study, patients were classified according to their serum uric acid level into 3 groups. Results: Women's GDM in group (I) showed that 3 (11.5%) were normal, 16 (61.5%) their fasting blood sugar levels (FBS) were high in 2nd trimester and 7 (26.9%) their FBS were high in both 2nd and 3rd trimesters while in group (II) 1 (3.8%) were normal, 9 (34.6%) their FBS were high in 2nd trimester and 16 (61.5%) their FBS were high in both 2nd and 3rd trimesters and in group (III) 1 (3.8%) was normal, 5 (19.2%) their FBS were high in 2nd trimester and 20 (76.9%) their FBS were high in both 2nd and 3rd trimesters. There was statistically significant differences between groups where P=0.007. Conclusion: First trimester serum uric acid levels are associated with subsequent development of IGT and GDM. The test has good predictive value for the diagnosis of GDM and it can be used in a risk assessment model.