Objective: To characterize the traditional Chinese medicine (TCM) syndromes of mild corona virus di-sease 2019(COVID-19) cases infected with Omicron variant for better prevention and treatment of COVID-19 infection. Methods A total of 188 mild covid -19 patients infected with Omicron variant infection in the northern section of Ruijin Hospital affiliated to Shanghai Jiao Tong university school of medicine and Jiahe Xinyuan shelter from March 24 through April 24, 2022 were enrolled, the tongue manifestation features, basic information, TCM syndrome and the time of negative turning were collected by the questionnaires. Results The mild cases were generally in good health status, with less than 20% patients having other major diseases. There was statistical significance in the median time of turning negative among different tongue shapes. The tongue coating indicated that the syndrome of cold-dampness stagnating, of evil-heat accumulating and dampness blocking in the lung pattern accounted for 38.8%, 34.5% and 23.4% of all cases. The syndrome of cold-dampness stagnating in the lung pattern and the syndrome of evil-heat accumulating in the lung pattern were found in majority of patient investigated. It took similar time for patients with different syndrome types to become COVID-19 virus negative (P>0.05). Conclusions The cold dampness was most common among mild COVID-19 patients with Omicron infection, who predominately presented syndrome of cold-dampness stagnating in the lung pattern.