We aim to clarify the efficacy of early palliative balloon pulmonary valvuloplasty (BPV) in neonates and young infants (< 60 days) with tetralogy of Fallot (TOF). We performed palliative BPV in 31 subjects, regardless of the presence of cyanosis, with Z score of the pulmonary valve diameter (PVD) less than − 2.00. Primary and secondary endpoints were to avoid early surgical interventions for subjects within 6 months of age and to undergo the pulmonary valve-sparing procedure at corrective surgery, respectively. We studied factors associated with these outcomes among them. BPV was performed at 19 days (14–33) of age and with a weight of 3.34 kg (3.02–3.65). Systemic oxygen saturation, Z score of the PVD, and pulmonary arterial index (PAI) were 87% (81–91), − 3.56 (− 4.15 to − 2.62), and 128 mm²/m² (102–157), respectively. There were 16 and 13 subjects who avoided early surgical interventions and transannular repair, respectively. At the primary endpoint, there was no significant difference in age, weight, systemic oxygen saturation, and Z score of the PVD and PAI between the groups. However, there was a significant difference in the infundibular morphology (severe: mild-to-moderate, 8:8 vs 13:2, P = 0.029) between the groups. We performed prophylactic BPV within 30 days after birth in 7 acyanotic TOF patients with severe infundibular obstruction, among whom 5 avoided early surgical intervention. At the secondary endpoint, there were no significant difference in weight, systemic oxygen saturation, but in sex, age at BPV, and Z score of the PVD. Early palliative BPV prevented early surgical intervention in half of the neonates and young infants with TOF, which depended upon the degree of infundibular obstruction. However, early palliative BPV did not contribute to avoid transanular patch right-ventricular outflow repair among them.