OBJECTIVETo present and analyze treatments and clinical outcomes of Chinese patients with influenza-like illness. METHODSWe conducted a multi-site observational study from December 2009 to April 2010. Patients with influenza-like illness from 45 hospitals were enrolled. Patients received Chinese herbal medicine (CHM), conventional treatments, or CHM plus conventional treatments (combination treatment) according to the guidelines for influenza A/H1N1 2009 in China. The primary outcomes were the time to alleviation of symptoms and the incidence of complications. The secondary outcomes were the time until becoming afebrile, incidence of severe illness, testing negative on an influenza A viral test, and total medical fees. RESULTSIn total, 5967 patients were enrolled. The percentages of patients prescribed CHM alone, conventional treatment, and combination treatment were 27.8%, 5.1%, and 67.7%, respectively. There were no significant differences in the time to alleviation of symptoms, incidence of complications, time to becoming afebrile, or rate of severe illness among the CHM, conventional, and combination treatment groups. The rates of testing negative on the influenza virus A rapid test and H1N1 virus test were 90.3% and 76.3%, respectively. However, significant differences were found in the total medical fees among the three groups: CHM treatments were more economical than the other two treatments. CONCLUSIONThe efficacy of CHM for influenza-like illness was not different from that of conventional treatments, but it was more economical.