OBJECTIVE: To study therapeutic effect and safety of early administration of oral ibuprofen in very low birth weight infants (VLBWIs) with patent ductus arteriosus (PDA). METHODS: A total of 64 symptomatic VLBWIs (within 24 hours after birth) with PDA confirmed by bedside Color Doppler ultrasound were randomly divided into two groups: treatment and control (n = 32 each). The treatment group was orally administered ibuprofen within 24 hours after birth at 10 mg/kg, followed 24 hours later by a second dose of 5 mg/kg and 48 hours later by a third dose of 5 mg/kg. The control group was treated with placebo (normal saline) at 1 mL/kg, followed 24 hours later by a second dose of 0.5 mL/kg and 48 hours later by a third dose of 0.5 mL/kg. The therapeutic efficacies and adverse effects in both groups were observed. RESULTS: The treatment group showed a significantly higher closure rate of ductus arterious than the control group after one course of treatment (84% vs 41%; P0.05). No obvious adverse effects were observed in both groups. CONCLUSIONS: Early administration of oral ibuprofen for treatment of PDA in VLBWIs can decrease the incidence rates of some early complications and shorten hospitalization time, but causes no significant adverse effects.