Objective: To observe the clinical efficacy of oral administration of Xiaoyong Prescription combined with external application of Jinhuang Ointment in the treatment of early stage of breast carbuncle during lactation and its effect on milk microflora. MethodsA total of 81 patients with breast carbuncle during lactation at the initial stage were randomly divided into control group (n=27) and treatment group (n=54) according to the proportion of 1∶2. Both groups were treated with Jinhuang Ointment externally. The control group was also given cefdinir capsules orally, while the treatment group was given Xiaoyong Prescription orally in the form of granules (modified according to syndromes). The course of treatment in both groups was 3 days. The clinical efficacy was observed, and the changes of quantitative scores of symptoms and signs of breast carbuncle, the positive rate of milk bacteria and specific bacteria quantity were compared.  Results:①The total effective rate of the treatment group and the control group were 90.7% and 74.1% respectively, and the clinical efficacy of the treatment group was better than that of the control group (P<0.05). ②The quantitative score of symptoms and signs of breast carbuncle in both groups decreased after treatment (P<0.05), and the quantitative score of breast carbuncle symptoms and signs in the treatment group was lower than that in the control group after treatment (P<0.05). ③The scores of breast carbuncle symptoms and signs including breast pain, skin redness, size and quantity of lumps, body temperature, percentage of neutrophils (N%) and C-reactive protein (CRP) in the two groups were all lower than those before treatment (P<0.05). After treatment, the differences in the scores of size and quantity of breast lumps between the groups were statistically significant (P<0.05). ④There was no significant difference in the positive rate of milk bacteria between the two groups before and after treatment (P>0.05). After treatment, the positive rate of milk bacteria in the treatment group was lower than that in the control group (P<0.05). ⑤There was no significant difference in the number of streptococcus, staphylococcus and lactobacillus in the milk of the two groups before and after treatment (P>0.05). There was no significant difference in the number of the above bacteria between the two groups before and after treatment (P>0.05).  Conclusion:Compared with oral administration of cefdinir combined with external application of Jinhuang Ointment, oral administration of Xiaoyong Prescription combined with external application of Jinhuang Ointment has more satisfactory efficacy on patients with early stage of breast carbuncle during lactation in resolving lumps, and can better reduce the positive rate of bacteria in milk.