Objective To evaluate the clinical protective effect of Influenza-Protective herbal sachet（ IPHS） on adult influenza. Methods During the influenza season in 2018

the volunteers who met the inclusion criteria were randomly divided into a herbal sachet group and a control group with 80 volunteers of each group. The herbal sachet group was given IPHS with functions of aroma avoiding filth（ recommended to be placed in the office

bedside

pillow

etc.）

to sniff from time to time

at least 3 times a day

no less than 1 minute each time. The contents were replaced after 2 weeks or after the aroma disappeared

and used it continuously for 2 months. The control group was not treated. All volunteers accepted 1 telephone interview per month. The incidence of influenza-like cases and fever

sore throat

cough

and fatigue symptoms were compared between groups. Results In the influenza-like cases in 1 month and 2 months

the number of volunteers with fever and cough in the herbal sachet group was smaller than the control group

but there was no significant differences between groups（ P > 0. 05）. And the number of volunteers with fever and sore throat was smaller than the control group（ P < 0. 05）. After 1 month

the number of volunteers with symptoms of fever

sore throat

cough

and fatigue was smaller than that of the control group

but the difference was not statistically significant（ P > 0. 05）. After 2 months

the number of the volunteers with above symptoms in the herbal sachet group was smaller than that of the control group（ P ≤0. 01）. Conclusion IPHS has the potential effect in prevention of seasonal influenza and the effect is more obvious after using two months.