Introduction Premature rupture of membranes (PROM) is one of the most common and important causes of premature births and peripartum mortality. Maternal antibiotic treatment affects the infantile prognosis. This study was conducted to compare the efficacy of Ampicillin and Cefotaxime administered for the parturients on neonatal outcomes. Material and Methods A comparison between the effects of Cefotaxime and Ampicillin on infantile complications of PROM was done in this clinical trial. Two hundred and twenty parturients with PROM who needed antibiotic therapy were randomized in two groups of control (Ampicillin) and intervention (Cefotaxime) treatments. The maternal/fetal statuses up to accouchement and the infants’ status up to transfer to neonatal intensive care unit, death, or discharge from hospital were followed. The Apgar score, cardiac, respiratory and nervous systems, infection, immaturity, asphyxia, and mortality rates were compared in both groups. Results The differences between the two groups were significant in: Apgar score min1 and min5, need for resuscitation, asphyxia, need for hospitalization, infection, and mortality rate. Conclusion Administration of Cefotaxime in parturients with PROM improved the Apgar scores and decreased respiratory complications, infection, asphyxia, mortality rate, and need for ICU hospitalization in infants.