Abstract: Objective:To investigate the X-ray findings of severe acute respiratory syndrome（SARS）.Methods:For459patients with SARS clinically diagnosed according to The Clinical Diagnostic Standards of Atypical Infectious pneumonia，Ministry Health of PR.China，the chest radiography was taken within the 15 days of admission.For abnormal foci，the size，lung area involved uni- or bilaterally and morphologic characteristics were analyzed.Results:The single focus was found in 156cases， multi foci in 303 cases.Unilateral lung involvement was found in 201 cases and bilateral in 258cases.The roentgenographic findings of SARS can be classified as following basic findings:local or extensive consolidation （n=272）；ground-glass opacification（n=55）；interstitia-l hyperplasia-like （IHL） lesion（n=62），which presented as area of network-like or collection of fine fiber hyperplasia and combination of these findings（n=70）.The ground-glass opacification located in pulmonary peripherally was never demonstrated before.Conclusion:The basic findings above can be demonstrated along or combination and groundglass opacification located in pulmonary peripherally could be considered as the characteristics findings of SARS.