Objective To evaluate the effect of penehyclidine particle size atomization in patients undergoing bronchoscopic needle aspiration (TBNA) nuder laryngeal mask anesthesia. Methods Selected patients undergoing EBUS-TBNA, aged 44-78 years, ASA II or III, were divided into two groups by random number table method: aerosolized ultra-fine particle size penehyclidine group (AP group) and aerosolized normal saline group (AS group), 25 cases in each group. TBNA was performed under general anesthesia with laryngeal mask ventilation. HR, SpO2, MAP, Ppeak and Pplat were recorded at the beginning (T1), intraoperative (T2) and end (T3) of TBNA operation. Anesthesia time, operation time, secretion volume during recovery and dry mouth/flush, urinary retention, delirium and pulmonary complications were recorded. Results There were no significant differences in gender, age, ASA classification, operation time, anesthesia time, MAP, HR, SpO2, Ppeak and Pplat at T1 and T3, and adverse drug reactions such as urinary retention and delirium among the three groups. Compared with AS group, AP group had lower Ppeak and Pplat pressures at T2, less secretions during recovery, and lower incidence of pulmonary complications (P0.05).Conclusion In general anesthesia TBNA, the atomized ultra-fine particle size penehyclidine can reduce airway spasm, and the occurrence of adverse reactions is less.