The invention relates to the technical field of expiration training devices. The invention discloses a 
lung expiration training device for 
cardiothoracic surgery patient 
nursing. The device comprisesa housing, the inner surface of the housing is fixedly connected with an expiration bag, an 
airflow groove is formed in the expiration bag, an air inlet plate is fixedly connected to the joint of thehousing and the expiration bag, the side, away from the expiration bag, of the air inlet plate is movably connected with an air 
nozzle, the end, away from the air inlet plate, of the air 
nozzle is movably connected with a boosting box, fan blades are movably connected to the upper side and the lower side of the boosting box, the end, away from the air 
nozzle, of the boosting box is movably connected with a rotating shaft, windward plates are movably connected to the upper and lower sides of the rotating shaft, a small amount of 
airflow with 
low oxygen content in the expiration bag is sucked tothe 
nose tip of the patient from the 
airflow groove, that is to say, content of 
oxygen inhaled by the patient is disturbed, and then respiratory organs of the patient are stimulated to inhale again,therefore, the effect of providing matched airflow assisting force according to the respiratory intensity of the patient to adjust the 
oxygen concentration to stimulate the cardio-pulmonary organs towork is achieved.