Abstract： Objective To investigate the effectiveness of oxytoein antagonist atosiban in the alternative rescue therapy of preterm labor.Methods Alternative toeolysis atosiban was given as rescue therapy to 35 women,who had received ritodrine or magnesium sulphate but failed,due to either progression of labour or intolerable adverse events.Atosiban was administered for up to 48 hours.Efficacy and tolerability were assessed based on the proportion of women who did not deliver and did not need alternative toeolytie therapy at 48 hours and 7 days after therapy initiation.The numbers of maternal adverse events and neonatal morbidity were also assessed.Results Efficacy and tolerability at 48 hours and 7 days after atosiban nitiation were 77％(27/35)and 60％(21/35).One woman presented drug-related side effects with mild nausea and omiting.Thirty-four women have delivered and one bigemina(28 weeks)is being followed-up.In 34 women,11 delivered before 28 gestational weeks,17 delivered after 28 gestational weeks,3 delivered after 34 weeks and 3 had term delivery.Pregnancies were rolonged by 4 hours to 14+2 weeks.There were nine neonatal deaths,with gestational ages less than 28 weeks at delivery.Conclusion xytocin antagonist atosiban could be given as alternative rescue therapy if therapy with ritodrine or magnesium sulphate fails in the treatment of preterm labor,and it is safe and effective.