The primary purpose of this study is to assess the efficacy and safety of Huashibaidu granule for the treatment of community-acquired pneumonia in children compared with placebo and to demonstrate the efficacy of Huashibaidu granule in improving clinical symptoms, removing pathogens, and shortening clinical course.

Subjects diagnosed as community-acquired pneumonia in children according to "Guideline for diagnosis and treatment of community-acquired pneumonia in Children (2019 version)" at Shanghai Children's Medical Center will be consecutively screened and eligible patients will be recruited. For each enrolled patient, basic information as well as basic medical condition will be collected by investigators. The subjects will be randomly assigned to the Huashibaidu group and the placebo group.

During the study, patients will receive Huashibaidu granule or placebo two times a day for five consecutive days. Both groups of patients will receive conventional Western medical observation and symptomatic treatment, including empiric anti-infective therapy (antibiotics) and symptomatic treatment such as antipyretic, expectorant and asthmatic. Do not use other traditional Chinese medicines, proprietary Chinese medicines, and antiviral drugs. Expectorants other than Ambroxol cannot be used.

After enrollment, investigator will evaluate and score patients' clinical symptoms at day 0, 1, 2, 3, 4, 5. Detection of biomarkers associated with infection, screening of pathogen and imaging examination will be conducted at day 0. And pharyngeal swab will be collected by investigator for tNGS at day 0, 3, 5.

Inclusion Criteria:

1. Han nationality.
2. Diagnosed as community-associated pneumonia in children according to "Guideline for diagnosis and treatment of community-acquired pneumonia in Children (2019 version)".
3. The first dose was given < 5 days from the onset of pneumonia (onset time is defined as the time of the first symptoms or signs of lower respiratory tract infection).
4. The guardian agrees to participate in the study and signs the informed consent form.

Exclusion Criteria:

1. The subject has severe respiratory distress, cyanosis, consciousness disorder, refusal to eat or dehydration.
2. The subject has chronic respiratory diseases, airway malformations, congenital heart disease, immune system diseases and other serious underlying diseases other than asthma.
3. The subject has moderate to severe persistent asthma or is in the acute asthma exacerbation.
4. The subject with influenza virus, pertussis, tuberculosis, fungi, and parasitic infections.
5. The subject with alanine aminotransferase (ALT) or aspartate aminotransferase (AST) 1.5 times higher than normal values in blood biochemical detection items, abnormal renal function, or troponin.
6. The subject with any other reason that investigators consider unsuitable to participate in this study.