For years the typical appearance of respiratory syncytial virus (RSV)-induced infection of the lower respiratory tract has been discussed. All available studies have led to different results. The aim of this study was to control these results, with 108 children. The age range was 1 day to 10 years (median 7 months). Within 72 h of admission, all children developed an RSV infection of the lower respiratory tract. Chest X-rays (pa-view) of 55 children under, and 53 children over, the age of 6 months (10/53>24 months) were evaluated. The diagnosis of RSV and the chest X-ray were mostly done on the same day. The major radiological findings of the two age-groups were compared by Wilcoxon's unpaired rank sum test. Major radiological findings were: normal chest X-ray (30%), central pneumonia (32%) or peribronchitis (26%). There was no statistical significance between the age-groups. Other findings were emphysema (11%), pleural effusion (6%), lobar- or broncho-pneumonia (each 6%), atelectasis (5%) or pneumothorax in one case. Therefore, the most common radiological findings in RSV-induced infection of the lower respiratory tract, supported by our results (RSV infection without bacterial superinfection) are central pneumonia, peribronchitis or normal chest X-ray. Thus an age-group separation into under or over 6 months is no longer necessary.