[INTRODUCTION - Air guns are frequently given to children as toys. Air guns have a pellet caliber of 0.17 or 0.22 and are propelled by compressed gas. Though they have little penetrating effect, they may cause life threatening injuries. Our purpose was to evaluate the frequency and the development of the diagnostic opportunities in children with air gun injuries during the last 30 years (1971-2000). PATIENTS AND METHODS - 52 patients (39 boys and 13 girls) were admitted to our pediatric surgery department due to of air gun injuries. The average age was 9 years (range 2 to 14 years). During the first fourteen years conventional X-ray (plain film and fluoroscopy), since 1984 ultrasonography and later (1986) CT has also been used for the diagnosis. RESULTS - In the first ten years 12 patients, in the second decade 18 patients and in the third ten years 22 patients were admitted and treated with air gun injuries. The sites of injury included upper, lower extremities (n=23), head (n=10), neck (n=5), chest (n=9) and the abdomen (n=5). The majority of patients had superficial injury and Xray plain films in different views were obtained, only. Major complication occured in 10 cases: bone fracture (n=1), soft tissue abscess (n=4) pneumothorax and hemothorax (n=4), bowel perforation (n=1). In these cases ultrasonography and/or CT was performed and they were helpful to establish the correct diagnosis. CONCLUSION - The general conception that air guns are toys, is basically wrong. The practice of placing air guns in the hands of children by their parents is very dangerous. On the basis of our results, the frequency of air gun injuries in children increased significantly in the last decade and the injuries were more serious than before (due to thew technologic modification of air gun). Ultrasonography and CT have important role in the diagnosis, but conventional X-ray remains the basic method in most of cases.]