Objective To observe the influence of Modified Mahuang Decoction （Ephedra Decoction） on the body temperature and TCM syndromes of patients with the fever caused by viral upper respiratory tract infection. Methods Totally 96 patients were randomized into a control group （43 cases） and a treatment group （53 cases）. The former was treated by the western medicine Oseltamivir capsule for oral taking and the latter treated by Modified Mahuang Decoction granule for oral taking. The course of treatment was 3 days. Changes of body temperature and TCM syndromes in the different time points of both groups were observed respectively before and after treatment. Results The body temperature of both groups was significantly lowered after treatment （P<0.05）. The effect in the control group started earlier than in the treatment group

while the antipyretic time in the treatment group was earlier than that in the control group. The clinical curative rate and TCM syndrome improvement of the treatment group were better than those of the control group （P<0.05）. Conclusion Modified Mahuang Decoction is effective in treating the fever due to viral upper respiratory tract infection.