Purpose: The purpose of this study is to determine the adverse perinatal outcomes in uncomplicated late preterm pregnancies with borderline oligohydramnios.Methods: A total of 430 pregnant women with an uncomplicated singleton pregnancy at a gestational age of 34+0-36+6 weeks were included. Borderline oligohydramnios was defined as an amniotic fluid index (AFI) of 5.1-8cm, which was measured using the four-quadrant technique. Adverse perinatal outcomes were compared between the borderline and normal AFI groups.Results: Approximately 107 of the 430 pregnant women were borderline AFI, and 323 were normal AFI. The demographic and obstetric characteristics were similar in both groups. Delivery <37 weeks, cesarean delivery for non-reassuring fetal heart-rate testing, meconium-stained amniotic fluid, Apgar 5min <7, transient tachypnea of the newborn, respiratory distress syndrome, neonatal intensive care unit, and hyperbilirubinemia were not statistically different between the groups (p=.054, p=.134, p=.749, p=0.858, p=.703, p=.320, p=.185, and p=.996, respectively). Although gestational age was full-term, induction of labor rates were significantly higher in the borderline AFI group (p=.040). In addition, fetal renal artery pulsatility index pulsatility index (PI) was significantly lower in the borderline AFI group than in the normal AFI group (p=.014).Conclusion: Our results indicated that borderline AFI was not a risk for adverse perinatal outcomes in uncomplicated, late preterm pregnancies.