Objective To investigate the clinical effect of Tanreqing Injection in treatment of fever children with cough and expectoration. Methods A total of 120 fever children with cough and expectoration admitted in our hospital from June 2018 to December 2019 were selected as research subjects and divided into control group and experimental group according to random number table method, with 60 cases in each group. The control group was treated with routine antiviral drugs, and the experimental group was treated with routine antiviral drugs and Tanreqing Injection. The clinical efficacy, relief time of expectoration, relief time of cough, recovery time of temperature, C-reactive protein (CRP), white blood cell count (WBC) and neutrophil ratio were compared between the two groups. Results The total effective rate of experimental group was higher than that of control group, and the difference was statistically significant (P<0.05). The relief time of expectoration, relief time of cough and recovery time of temperature in experimental group were shorter than those in control group, and the differences were statistically significant (P<0.05). The levels of CRP, WBC and neutrophil ratio in two groups after treatment were lower than those before treatment, and the differences were statistically significant (P<0.05). The levels of CRP, WBC and neutrophil ratio in experimental group after treatment were lower than those in control group, and the differences were statistically significant (P<0.05). Conclusion Tanreqing Injection in treatment of fever children with cough and expectoration has good effects, it can shorten relief time of clinical symptoms, decrease the levels of inflammatory factors, relieve the symptoms of fever and cough.