Beta2 agonists mostly activate beta2 adrenergic receptors, which play a powerful therapeutic role in the treatment of asthma. Their main functions include diastole of bronchial smooth muscle, and also have anti-inflammatory effects by inhibiting inflammatory cells and inhibiting the release of inflammatory mediators. In addition, it can also inhibit the release of neurotransmitters to achieve the effect of further diastole bronchial smooth muscle. It also has the effect of promoting the secretion of bronchial mucus glands and increasing the oscillation of bronchial cilia to deliver secretions. Some β2 agonists have certain cough suppressant effects and can be used for acute and chronic coughs caused by various reasons. In clinical practice, β2 agonists are mostly used in the treatment of airway obstructive diseases such as bronchial asthma and chronic obstructive pulmonary disease, and they are often combined with inhaled glucocorticoids and cholinergic receptor blockers, which have synergistic therapeutic effects.