Gestational diabetes mellitus is defined as carbohydrate intolerance of variable severity first diagnosed during pregnancy. Although gestational diabetes mellitus is associated with serious obstetric and perinatal complications, there has not been an appropriately controlled trial demonstrating the efficacy of widespread screening for gestational diabets mellitus in Korea. Our purpose was to determine how obstetricians are currently implementing screening tests to diagnose and manage gestational diabetes mellitus. Questionnaires were mailed to 85 obstetricians and perinatologists in hospitals with obstetrics and gynecology residency programs. 28(33%) of specialists responded and the results were summarized. Agreement is lacking regarding the methods of screening and diagnostic tests, selection of test subjects, test threshold of screening, glucose solutions, and interpretations. Arguments concerning screening for gestational diabetes are reviewed and some suggestions for future studies in Korea are introduced.