Background <p>Twins are associated with an increased risk of premature birth, a major cause of neonatal morbidity and mortality. Antenatal corticosteroid treatment (ACT) is the main intervention to improve neonatal outcomes in unavoidable preterm births. Our aim was to investigate the association between neonatal outcome and ACT in twin pregnancies with late preterm birth, where the effects of corticosteroids have not been adequately studied.</p> Methods <p>Women with dichorionic-diamniotic twins who had a late preterm birth between 2017 and 2021 at a large referral hospital providing tertiary care and medical training were retrospectively analyzed. Women who met the inclusion criteria were divided into three groups: No ACT (<i>n</i> = 209), ACT &lt; 34 weeks’ gestation (<i>n</i> = 76) and ACT ≥ 34 weeks’ gestation (<i>n</i> = 67). The groups were compared with regard to adverse neonatal complications. Primary outcome measures were composite respiratory and composite neonatal outcomes. Logistic regression analysis was used to determine additional potential predictors of neonatal outcome.</p> Results <p>Composite respiratory and composite neonatal outcomes did not differ significantly between groups. Birth gestational age, birthweight and ACT before 34 weeks’ gestation were independently associated with favorable composite respiratory outcome, composite neonatal outcome and a lower neonatal intensive care unit admission rate. Female sex was independently associated with favorable composite respiratory outcome and a lower neonatal intensive care unit admission rate, while birth gestational age and birthweight were independently associated with a lower rate of hypoglycemia.</p> Conclusion <p>ACT at or after 34 weeks’ gestation was not associated with better neonatal outcomes in dichorionic-diamniotic twins born late preterm and was associated with a higher rate of neonatal hypoglycemia than those not treated with corticosteroids.</p>