Objective:To study the short-term clinical outcomes of different courses of antenatal corticosteroids (ACS) for preterm twins.Methods:From January 2017 to December 2021, preterm twins with gestational age (GA) 24-34 weeks admitted to the neonatal ward of our hospital and received ACS were retrospectively studied. The infants were assigned into single-course group, partial-course group and multiple-course group according to ACS courses. The short-term clinical outcomes were compared among the groups. SPSS software version 25.0 was used for statistical analysis.Results:A total of 286 infants were enrolled in this study, including 128 in single-course group, 89 in partial-course group and 69 in multiple-course group. Compared with single-course group, the risks of neonatal respiratory distress syndrome (RDS) in both partial-course group ( OR=2.332, 95% CI 1.028-5.293, P=0.043) and multiple-course group ( OR=3.872, 95% CI 1.104-13.584, P=0.034) were higher. The birth length in multiple-course group ( β=-0.016, 95% CI -0.029 - -0.002, P=0.024) was lower than single-course group. Conclusions:The risks of neonatal RDS in preterm twins are higher in partial-course and multiple-course of ACS. A full course of ACS should be used to prevent neonatal RDS until further evidence of effectiveness is available.