Objective: To explore the changes of tongue pictures in the developing process of disease in patients with severe acute respiratory syndrome (SARS), and to compare the tongue pictures of SARS patients with those of suspected SARS patients. Methods: Materials of tongue picture were dynamically collected from 34 SARS patients and 35 suspected SARS patients, and the difference and similarity between them were analyzed. Meanwhile, the changes in clinic symptoms and tongue picture after integrative medicinal treatment were observed. Results: Characteristics of tongue picture in SARS patients were changed along with the progress of the disease, showing that there existed a tendency of the pathogen invading from exterior to interior, from surface to the deep. Also the tongue pictures were varied due to the coexistence of dampness pathogen; the time of the early stage was generally 1-1.5 days, shorter than that of other stages.While in the patients with suspected SARS, the tongue picture was mostly red with thin white or yellow coating, comparatively steady and showing no obvious change along with the development of the disease. Conclusion: Observing the tongue picture and its changes in different stages can be helpful to understanding the property of pathogenic evil and its developing rules, thus offering a basis for clinical treatment.