Inclusion Criteria:  aged 4-11 years old GINA (Global Initiative for Asthma) guideline belong to mild to moderate asthmatic children regular use low dose ICS+ LABA or medium dose ICS at least one month  Exclusion Criteria:  asthma with acute exacerbation or ever has used systemic steroids in recent one month psychiatric disease or behavior disorder ever has received Chinese herbal medicine or other traditional Chinese medicine treatment in recent two weeks