In the treatment of threatened preterm labor，timely and effective application of tocolytic drugs is the most important treatment method.The commonly used tocolytic drugs in clinic include：β-adrenergic receptor agonists，calcium channel blockers，oxytocin receptor antagonists，prostaglandin synthetase inhibitors and magnesium sulfate.However，the effects and clinical characteristics of each tocolytic drugs are different.This article summarizes the research progress of several commonly used tocolytic drugs in the treatment of threatened preterm labor.