Abstract: Pulmonary fungal infections spread rapidly and need timely intervention of medication. Tissue necrosis and local pulmonary structural damage occur in a short period of time. If fungal infections are controlled by effective antifungal drugs or limited by the patient's autoimmune system, fibrous connective tissue and granulation tissue can be formed quickly. Amphotericin B is a polyene antifungal agent with a wide antifungal spectrum and strong effect. When intravenously applied， the concentration of amphotericin B commonly attained in lungs has only bacteriostatic effect on fungus, with high toxicity and adverse reactions. The absorption through the airway mucosa is low and slow and the irritation is not strong. According to these characteristics, local injection of amphotericin B via bronchoscopy has a great advantage, which is worthy of clinical promotion. Based on the guidelines and clinical experience, the theoretical basis and operation procedure of local instillation of amphotericin B into lungs by bronchoscopy are described in detail，including pharmacological mechanism, local dose, solution concentration and the detailed method of operation of it.

Key words: amphotericin B, bronchoscopy, lung diseases, fungal