Objective,2,To observe the clinical effect of internal and external administration of Senecionis Scandentis Herba Preparations in the treatment of acute mastitis during lactation.,Methods,2,Ninety-two patients with acute mastitis during lactation received between January 2020 and August 2021 in Dongzhimen Hospital of Beijing University of Chinese Medicine were selected as the research subjects. They were divided into control group （,n,=47） and observation group （,n,=45） by random number table method. The control group were treated with antibiotics，and the observation group were treated with internal and external administration of Senecionis Scandentis Herba Preparations，both groups for 7 days as one course. The clinical effective rate and the recovery of symptoms were compared between the two groups，the changes of inflammatory indicators and immune factors of two groups were observed.,Results,2,The clinical effective rate in the observation group was higher than that in the control group with the difference statistically significant （,P,<,0.05）. The subsiding time of skin redness and swelling， pain disappearance time， body temperature recovery time， subsiding time of lump， and time for promoting lactation in the observation group were shorter than those in the control group with the difference statistically significant（,P,<,0.05）. The levels of white blood cell （WBC）， C-reactive protein （CRP）， prostaglandin E,2,（PGE,2,）， immunoglobulin G （IgG）， IgM and IgA in the observation group after 3 days of treatment were lower than those in the control group with the difference statistically significant （,P,<,0.05）.,Conclusion,2,Internal and external administration of Senecionis Scandentis Herba Preparations can shorten the recovery process of acute mastitis during lactation and reduce the level of inflammation and immune-related factors.