Clinical observation is made on the total 676 cases of foreign body in the air and food passages. The entire foreign body cases, who have visited ENT dept. of Kyungpook National University Hospital, from 1952 to 1971, are included in this study. 

Results : 
1) Number of foreign body cases is approximated to 1.5% of total number of new patient at ENT OPD. The most of foreign body are found in the food passage (86.5%), whereas in the air passage, only 91 cases (13.5%). The ratio between food passage vs. air passage is 6.4 : 1. 2) In the case of food passage, a coin is the most frequently found (34.9%) and a bone piece is the next (32.1%). In the case of air passage, 24 cases are kind of corn and 12 cases are a bone piece in the next order. The entire coin cases are found exclusibely in the age group of below 15, the corn is exclusively to the age group of below 5. 3) In the locality of the air and food passages, the first isthmus of the esophagus is the most frequently lodged site (71.1%) and the third isthmus is only 3.3%. In the air passage case, the bronchus is the most frequently involved (40.7%) and right to left ratio is 6.4 : 1. 4) In the both case of the air and food passages, male seem more frequently involved than female, 57.6% in food passage and 61.5% in the air passage. In the food passage cases, the age group of below 10 occupies more than half of the total cases up to 58.0%, and is the air passage, the same age group occupies the most up to 84.6%. Its worthwhile to mention that the 13 days old infant is also a victim of the esophagus foreign body. 5) Within three days of accident, the most cases are removed ; 81.2% in food passage, 55.0% in air passage. 6) The accidental mishap seems the most frequently encountered causative factor. Especially in those 62 case of esophageal stricture, their carelessness seems to play more important role to this repeated tendency rather than narrowing itself.